[Title 40 CFR ]
[Code of Federal Regulations (annual edition) - July 1, 2017 Edition]
[From the U.S. Government Publishing Office]



[[Page i]]

          

          Title 40

Protection of Environment


________________________

Part 1060 to End

                         Revised as of July 1, 2017

          Containing a codification of documents of general 
          applicability and future effect

          As of July 1, 2017
                    Published by the Office of the Federal Register 
                    National Archives and Records Administration as a 
                    Special Edition of the Federal Register

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                            Table of Contents



                                                                    Page
  Explanation.................................................       v

  Title 40:
          Chapter I--Environmental Protection Agency 
          (Continued)                                                3
          Chapter IV--Environmental Protection Agency and 
          Department of Justice                                    455
          Chapter V--Council on Environmental Quality              463
          Chapter VI--Chemical Safety and Hazard Investigation 
          Board                                                    511
          Chapter VII--Environmental Protection Agency and 
          Department of Defense; Uniform National Discharge 
          Standards for Vessels of the Armed Forces                547
          Chapter VIII--Gulf Coast Ecosystem Restoration 
          Council                                                  563
  Finding Aids:
      Table of CFR Titles and Chapters........................     587
      Alphabetical List of Agencies Appearing in the CFR......     607
      List of CFR Sections Affected...........................     617

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                     ----------------------------

                     Cite this Code: CFR
                     To cite the regulations in 
                       this volume use title, 
                       part and section number. 
                       Thus, 40 CFR 1060.1 refers 
                       to title 40, part 1060, 
                       section 1.

                     ----------------------------

[[Page v]]



                               EXPLANATION

    The Code of Federal Regulations is a codification of the general and 
permanent rules published in the Federal Register by the Executive 
departments and agencies of the Federal Government. The Code is divided 
into 50 titles which represent broad areas subject to Federal 
regulation. Each title is divided into chapters which usually bear the 
name of the issuing agency. Each chapter is further subdivided into 
parts covering specific regulatory areas.
    Each volume of the Code is revised at least once each calendar year 
and issued on a quarterly basis approximately as follows:

Title 1 through Title 16.................................as of January 1
Title 17 through Title 27..................................as of April 1
Title 28 through Title 41...................................as of July 1
Title 42 through Title 50................................as of October 1

    The appropriate revision date is printed on the cover of each 
volume.

LEGAL STATUS

    The contents of the Federal Register are required to be judicially 
noticed (44 U.S.C. 1507). The Code of Federal Regulations is prima facie 
evidence of the text of the original documents (44 U.S.C. 1510).

HOW TO USE THE CODE OF FEDERAL REGULATIONS

    The Code of Federal Regulations is kept up to date by the individual 
issues of the Federal Register. These two publications must be used 
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    To determine whether a Code volume has been amended since its 
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Sections Affected (LSA),'' which is issued monthly, and the ``Cumulative 
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EFFECTIVE AND EXPIRATION DATES

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Code a note has been inserted to reflect the future effective date. In 
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inserted following the text.

OMB CONTROL NUMBERS

    The Paperwork Reduction Act of 1980 (Pub. L. 96-511) requires 
Federal agencies to display an OMB control number with their information 
collection request.

[[Page vi]]

Many agencies have begun publishing numerous OMB control numbers as 
amendments to existing regulations in the CFR. These OMB numbers are 
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PAST PROVISIONS OF THE CODE

    Provisions of the Code that are no longer in force and effect as of 
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Code users may find the text of provisions in effect on any given date 
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previous annual editions of the LSA. For changes to the Code prior to 
2001, consult the List of CFR Sections Affected compilations, published 
for 1949-1963, 1964-1972, 1973-1985, and 1986-2000.

``[RESERVED]'' TERMINOLOGY

    The term ``[Reserved]'' is used as a place holder within the Code of 
Federal Regulations. An agency may add regulatory information at a 
``[Reserved]'' location at any time. Occasionally ``[Reserved]'' is used 
editorially to indicate that a portion of the CFR was left vacant and 
not accidentally dropped due to a printing or computer error.

INCORPORATION BY REFERENCE

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established by statute and allows Federal agencies to meet the 
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to materials already published elsewhere. For an incorporation to be 
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This material, like any other properly issued regulation, has the force 
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alphabetical list of agencies publishing in the CFR are also included in 
this volume.

[[Page vii]]

    An index to the text of ``Title 3--The President'' is carried within 
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the revision dates of the 50 CFR titles.

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in the Code of Federal Regulations.

INQUIRIES

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    Oliver A. Potts,
    Director,
    Office of the Federal Register.
    July 1, 2017.







[[Page ix]]



                               THIS TITLE

    Title 40--Protection of Environment is composed of thirty-seven 
volumes. The parts in these volumes are arranged in the following order: 
Parts 1-49, parts 50-51, part 52 (52.01-52.1018), part 52 (52.1019-
52.2019), part 52 (52.2020-end of part 52), parts 53-59, part 60 (60.1-
60.499), part 60 (60.500-end of part 60, sections), part 60 
(Appendices), parts 61-62, part 63 (63.1-63.599), part 63 (63.600-
63.1199), part 63 (63.1200-63.1439), part 63 (63.1440-63.6175), part 63 
(63.6580-63.8830), part 63 (63.8980-end of part 63), parts 64-71, parts 
72-79, part 80, part 81, parts 82-86, parts 87-95, parts 96-99, parts 
100-135, parts 136-149, parts 150-189, parts 190-259, parts 260-265, 
parts 266-299, parts 300-399, parts 400-424, parts 425-699, parts 700-
722, parts 723-789, parts 790-999, parts 1000-1059, and part 1060 to 
end. The contents of these volumes represent all current regulations 
codified under this title of the CFR as of July 1, 2017.

    Chapter I--Environmental Protection Agency appears in all thirty-
seven volumes. Regulations issued by the Council on Environmental 
Quality, including an Index to Parts 1500 through 1508, appear in the 
volume containing parts 1060 to end. The OMB control numbers for title 
40 appear in Sec.  9.1 of this chapter.

    For this volume, Michele Bugenhagen was Chief Editor. The Code of 
Federal Regulations publication program is under the direction of John 
Hyrum Martinez, assisted by Stephen J. Frattini.

[[Page 1]]



                   TITLE 40--PROTECTION OF ENVIRONMENT




                  (This book contains part 1060 to End)

  --------------------------------------------------------------------
                                                                    Part

chapter i--Environmental Protection Agency (Continued)......        1060

chapter iv--Environmental Protection Agency and Department 
  of Justice................................................        1400

chapter v--Council on Environmental Quality.................        1500

chapter vi--Chemical Safety and Hazard Investigation Board..        1600

chapter vii--Environmental Protection Agency and Department 
  of Defense; Uniform National Discharge Standards for 
  Vessels of the Armed Forces...............................        1700

chapter viii--Gulf Coast Ecosystem Restoration Council......        1800

[[Page 3]]



         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)




  --------------------------------------------------------------------


  Editorial Note: Nomenclature changes to chapter I appear at 65 FR 
47324, 47325, Aug. 2, 2000, and 66 FR 34375, 34376, June 28, 2001.

                  SUBCHAPTER U--AIR POLLUTION CONTROLS
Part                                                                Page
1060            Control of evaporative emissions from new 
                    and in-use nonroad and stationary 
                    equipment...............................           5
1065            Engine-testing procedures...................          45
1066            Vehicle-testing procedures..................         280
1068            General compliance provisions for highway, 
                    stationary, and nonroad programs........         379
1074            Preemption of state standards and procedures 
                    for waiver of federal preemption for 
                    nonroad engines and nonroad vehicles....         451
1075-1099       [Reserved]

[[Page 4]]







[[Page 5]]



                   SUBCHAPTER U_AIR POLLUTION CONTROLS





PART 1060_CONTROL OF EVAPORATIVE EMISSIONS FROM NEW AND IN-USE NONROAD
AND STATIONARY EQUIPMENT--Table of Contents



                  Subpart A_Overview and Applicability

Sec.
1060.1 Which products are subject to this part's requirements?
1060.5 Do the requirements of this part apply to me?
1060.10 How is this part organized?
1060.15 Do any other CFR parts apply to me?
1060.30 Submission of information.

          Subpart B_Emission Standards and Related Requirements

1060.101 What evaporative emission requirements apply under this part?
1060.102 What permeation emission control requirements apply for fuel 
          lines?
1060.103 What permeation emission control requirements apply for fuel 
          tanks?
1060.104 What running loss emission control requirements apply?
1060.105 What diurnal requirements apply for equipment?
1060.120 What emission-related warranty requirements apply?
1060.125 What maintenance instructions must I give to buyers?
1060.130 What installation instructions must I give to equipment 
          manufacturers?
1060.135 How must I label and identify the engines and equipment I 
          produce?
1060.137 How must I label and identify the fuel-system components I 
          produce?

                 Subpart C_Certifying Emission Families

1060.201 What are the general requirements for obtaining a certificate 
          of conformity?
1060.202 What are the certification requirements related to the general 
          standards in Sec. 1060.101?
1060.205 What must I include in my application?
1060.210 What records should equipment manufacturers keep if they do not 
          apply for certification?
1060.225 How do I amend my application for certification?
1060.230 How do I select emission families?
1060.235 What emission testing must I perform for my application for a 
          certificate of conformity?
1060.240 How do I demonstrate that my emission family complies with 
          evaporative emission standards?
1060.250 What records must I keep?
1060.255 What decisions may EPA make regarding my certificate of 
          conformity?

                Subpart D_Production Verification Testing

1060.301 Manufacturer testing.
1060.310 Supplying products to EPA for testing.

                        Subpart E_In-Use Testing

1060.401 General Provisions.

                        Subpart F_Test Procedures

1060.501 General testing provisions.
1060.505 Other procedures.
1060.510 How do I test EPA Low-Emission Fuel Lines for permeation 
          emissions?
1060.515 How do I test EPA Nonroad Fuel Lines and EPA Cold-Weather Fuel 
          Lines for permeation emissions?
1060.520 How do I test fuel tanks for permeation emissions?
1060.521 How do I test fuel caps for permeation emissions?
1060.525 How do I test fuel systems for diurnal emissions?

                 Subpart G_Special Compliance Provisions

1060.601 How do the prohibitions of 40 CFR 1068.101 apply with respect 
          to the requirements of this part?
1060.605 Exemptions from evaporative emission standards.
1060.640 What special provisions apply to branded equipment?

          Subpart H_Averaging, Banking, and Trading Provisions

1060.701 Applicability.
1060.705 How do I certify components to an emission level other than the 
          standard under this part or use such components in my 
          equipment?

          Subpart I_Definitions and Other Reference Information

1060.801 What definitions apply to this part?
1060.805 What symbols, acronyms, and abbreviations does this part use?
1060.810 What materials does this part reference?
1060.815 What provisions apply to confidential information?
1060.820 How do I request a hearing?
1060.825 What reporting and recordkeeping requirements apply under this 
          part?

    Authority: 42 U.S.C. 7401-7671q.

[[Page 6]]


    Source: 73 FR 59298, Oct. 8, 2008, unless otherwise noted.



                  Subpart A_Overview and Applicability



Sec. 1060.1  Which products are subject to this part's requirements?

    (a) The standards and other requirements in this part 1060 apply to 
the fuel lines, fuel tanks, couplings and fittings, and fuel caps used 
or intended to be used in the following categories of new engines and 
equipment that are fueled with a volatile liquid fuel (such as gasoline, 
but not including diesel fuel), and to the equipment in which these 
components are installed, starting with the model years shown in Table 1 
to this section:
    (1) Compression-ignition engines we regulate under 40 CFR part 1039. 
This includes stationary compression-ignition engines we regulate under 
the provisions of 40 CFR part 1039, as indicated under 40 CFR part 60, 
subpart IIII. See the evaporative emission standards specified in 40 CFR 
1048.105. These engines are considered to be Large SI engines for 
purposes of this part 1060.
    (2) Marine compression-ignition engines we regulate under 40 CFR 
part 1042. See the evaporative emission standards specified in 40 CFR 
1045.112. These engines are considered to be Marine SI engines for 
purposes of this part 1060.
    (3) Marine SI engines we regulate under 40 CFR part 1045. See the 
evaporative emission standards specified in 40 CFR 1045.112.
    (4) Large SI engines we regulate under 40 CFR part 1048. This 
includes stationary spark-ignition engines subject to standards under 40 
CFR parts 1048 or 1054 as indicated in 40 CFR part 60, subpart JJJJ. See 
the evaporative emission standards specified in 40 CFR 1048.105.
    (5) Recreational vehicles and engines we regulate under 40 CFR part 
1051 (such as snowmobiles and off-highway motorcycles). This includes 
highway motorcycles subject to standards under 40 CFR part 1051 as 
indicated in 40 CFR part 86, subpart E since these motorcycles are 
considered to be recreational vehicles for purposes of this part 1060. 
See the evaporative emission standards specified in 40 CFR 1051.110.
    (6) Small SI engines we regulate under 40 CFR part 1054. See the 
evaporative emission standards specified for handheld engines in 40 CFR 
1054.110 and for nonhandheld engines in 40 CFR 1054.112.
    (7) Portable marine fuel tanks and fuel lines associated with such 
fuel tanks must meet evaporative emission standards specified in 40 CFR 
1045.112. Portable nonroad fuel tanks and fuel lines associated with 
such fuel tanks must also meet evaporative emission standards specified 
in 40 CFR 1045.112, whether or not they are used with marine vessels. 
Portable nonroad fuel tanks are considered to be portable marine fuel 
tanks for purposes of this part 1060.
    (b) The regulations in this part 1060 apply for new replacement 
components used with any of the engines or equipment specified in 
paragraph (a) of this section as described in Sec. 1060.601.
    (c) Fuel caps are subject to evaporative emission standards at the 
point of installation on a fuel tank. If a fuel cap is certified for use 
with Marine SI engines or Small SI engines under the optional standards 
of Sec. 1060.103, it is subject to all the requirements of this part 
1060 as if these optional standards were mandatory.
    (d) This part 1060 does not apply to any diesel-fueled engine or any 
other engine that does not use a volatile liquid fuel. In addition, this 
part does not apply to any engines or equipment in the following 
categories even if they use a volatile liquid fuel:
    (1) Light-duty motor vehicles (see 40 CFR part 86).
    (2) Heavy-duty motor vehicles and heavy-duty motor vehicle engines 
(see 40 CFR part 86). This part 1060 also does not apply to fuel systems 
for nonroad engines where such fuel systems are subject to part 86 
because they are part of a heavy-duty motor vehicle.
    (3) Aircraft engines (see 40 CFR part 87).
    (4) Locomotives (see 40 CFR part 92 and 1033).
    (5) Land-based nonroad diesel engines we regulate under 40 CFR part 
89.
    (6) Marine diesel engines we regulate under 40 CFR part 89, 94, or 
1042.

[[Page 7]]

    (7) Land-based spark-ignition engines at or below 19 kW that we 
regulate under 40 CFR part 90. Note that there are provisions in 40 CFR 
part 90 that reference specific portions of this part 1060.
    (8) Marine spark-ignition engines we regulate under 40 CFR part 91.
    (e) This part 1060 does not apply for fuel lines made wholly of 
metal.

                              Table 1 to Sec. 1060.1--Part 1060 Applicability \a\
----------------------------------------------------------------------------------------------------------------
      Equipment category or            Fuel line                                                 Running loss
           subcategory                permeation        Tank permeation    Diurnal emissions       emissions
----------------------------------------------------------------------------------------------------------------
Marine SI--portable marine fuel   January 1, 2009     January 1, 2011...  January 1, 2010...  Not applicable.
 tanks.                            \b\.
Marine SI--personal watercraft..  January 1, 2009...  Model year 2011...  Model year 2010...  Not applicable.
Marine SI--other vessels with     January 1, 2009     Model year 2012...  July 31, 2011.....  Not applicable.
 installed fuel tanks.             \b\.
Large SI........................  Model year 2007...  Not applicable....  Model year 2007     Model year 2007.
                                                                           (includes tank
                                                                           permeation).
Recreational vehicles...........  Model year 2008...  Model year 2008...  Not applicable....  Not applicable.
Small SI--handheld..............  Model year 2012     Model year 2010     Not applicable....  Not applicable.
                                   \c\.                \d\.
Small SI--Class I nonhandheld...  January 1, 2009...  Model year 2012...  Not applicable \e\  Model year 2012.
Small SI--Class II nonhandheld..  January 1, 2009...  Model year 2011...  Not applicable \e\  Model year 2011.
----------------------------------------------------------------------------------------------------------------
\a\ Implementation is based on the date of manufacture of the equipment. Where we do not identify a specific
  date, the emission standards start to apply at the beginning of the model year.
\b\ January 1, 2011 for primer bulbs. Standards phase in for under-cowl fuel lines on outboard engines, by
  length: 30% in 2010, 60% in 2011, 90% in 2012-2014, 100% in 2015.
\c\ 2013 for small-volume emission families that do not include cold-weather fuel lines.
\d\ 2011 for structurally integrated nylon fuel tanks and 2013 for all small-volume emission families.
\e\ Manufacturers may optionally meet diurnal standards as specified in Sec. 1060.105(e).



Sec. 1060.5  Do the requirements of this part apply to me?

    The requirements of this part are generally addressed to the 
manufacturers that are subject to this part's requirements as described 
in paragraph (a) of this section. The term ``you'' generally means the 
manufacturer or manufacturers that are subject to these requirements. 
Paragraphs (b) through (e) of this section describe which manufacturers 
may or must certify their products. (Note: Sec. 1060.601(f) allows the 
certification responsibility to be delegated in certain circumstances.)
    (a) Overall responsibilities. Manufacturers of the engines, 
equipment, and fuel-system components described in Sec. 1060.1 are 
subject to the standards and other requirements of this part 1060 except 
as otherwise noted. Multiple manufacturers may be subject to these 
standards and other requirements. For example, when a Small SI equipment 
manufacturer buys fuel line manufactured by another person and installs 
them in its equipment, both the equipment manufacturer and the fuel line 
manufacturer are subject to the standards and other requirements of this 
part. The following provisions apply in such cases:
    (1) Each person meeting the definition of manufacturer for a product 
that is subject to the standards and other requirements of this part 
must comply with such requirements. However, if one person complies with 
a specific requirement for a given product, then all manufacturers are 
deemed to have complied with that specific requirement. For example, if 
a Small SI equipment manufacturer uses fuel lines manufactured and 
certified by another company, the equipment manufacturer is not required 
to obtain a certificate with respect to the fuel line emission 
standards. Such an equipment manufacturer remains subject to the 
standards and other requirements of this part. However, where a 
provision requires a specific manufacturer to comply with certain 
provisions, this paragraph (a) does not change or modify such a 
requirement. For example, this

[[Page 8]]

paragraph (a) does not allow you to rely on another company to certify 
instead of you if we specifically require you to certify.
    (2) The requirements of subparts C and D of this part apply to the 
manufacturer that obtains the certificate of conformity. Other 
manufacturers are required to comply with the requirements of subparts C 
and D of this part only when we send notification. In our notification, 
we will specify a reasonable period for complying with the requirements 
identified in the notice. See Sec. 1060.601 for the applicability of 40 
CFR part 1068 to these other manufacturers.
    (3) Certificate holders are responsible for meeting all applicable 
requirements even if other manufacturers are also subject to those 
requirements.
    (b) Marine SI. Certify vessels, engines, and fuel-system components 
as follows:
    (1) Component manufacturers must certify their fuel lines and fuel 
tanks intended for installation with Marine SI engines and vessels under 
this part 1060, except as allowed by Sec. 1060.601(f). This includes 
permeation and diurnal emission standards.
    (2) Vessel manufacturers are subject to all the requirements of this 
part 1060 that apply to Marine SI engines and fuel systems. However, 
they must certify to the emission standards specified in Sec. Sec. 
1060.102 through 1060.105 only if one or more of the following 
conditions apply:
    (i) Vessel manufacturers must certify fuel system components they 
install in their vessels if the components are not certified to meet all 
applicable evaporative emission standards, including both permeation and 
diurnal standards. This would include vessel manufacturers that make 
their own fuel tanks. Vessel manufacturers would need to act as 
component manufacturers to certify under this part 1060.
    (ii) Vessel manufacturers must certify their vessels only if they 
intend to generate or use evaporative emission credits. Vessel 
manufacturers would certify under part 40 CFR part 1045 using the 
emission-credit provisions in subpart H of that part to demonstrate 
compliance with the emission standard.
    (3) Engine manufacturers must meet all the requirements of this part 
1060 that apply to vessel manufacturers for all fuel-system components 
they install on their engines. For example, engine manufacturers that 
install under-cowl fuel lines and fuel tanks must comply with the 
requirements specified for vessel manufacturers with respect to those 
components.
    (c) Large SI. Certify engines, equipment, and fuel-system components 
as follows:
    (1) Engine manufacturers must certify their engines under 40 CFR 
part 1048.
    (2) Equipment manufacturers and component manufacturers may certify 
fuel lines and fuel tanks intended for use with Large SI engines under 
this part 1060.
    (d) Recreational vehicles. Certify vehicles, engines and fuel-system 
components as follows:
    (1) Vehicle manufacturers must certify their vehicles under 40 CFR 
part 1051.
    (2) Engine manufacturers must meet all the requirements of 40 CFR 
part 1051 that apply to vehicle manufacturers for all fuel-system 
components they install on their engines. For example, engine 
manufacturers that install fuel-line segments on the engines they ship 
to vehicle manufacturers must comply with the requirements specified for 
equipment manufacturers with respect to those components.
    (3) Component manufacturers may certify fuel lines and fuel tanks 
intended for recreational vehicles under this part 1060.
    (e) Small SI. Certify engines, equipment, and fuel-system components 
as follows:
    (1) Component manufacturers must certify their fuel lines and fuel 
tanks intended for Small SI engines and equipment under this part 1060, 
except as allowed by Sec. 1060.601(f).
    (2) Equipment manufacturers must certify fuel system components they 
install in their equipment if the components are not certified to meet 
applicable evaporative emission standards. Equipment manufacturers would 
need to act as component manufacturers to certify fuel-system components 
under this part 1060.

[[Page 9]]

    (3) Engine manufacturers must meet all the requirements of this part 
1060 that apply to equipment manufacturers for all fuel-system 
components they install on their engines. Engine manufacturers that 
produce Small SI engines with complete fuel systems are considered the 
equipment manufacturers for those engines under this part 1060.
    (4) Equipment manufacturers must certify their equipment and are 
subject to all the requirements of this part 1060; however, this does 
not apply for equipment using portable nonroad fuel tanks.
    (f) Summary of certification responsibilities. Tables 1 through 3 of 
this section summarize the certification responsibilities for different 
kinds of manufacturers as described in paragraphs (b) through (e) of 
this section. The term ``No'' as used in the tables means that a 
manufacturer is not required to obtain a certificate of conformity under 
paragraphs (b) through (e) of this section. In situations where multiple 
manufacturers are subject to the standards and other requirements of 
this part, such a manufacturer must nevertheless certify if the 
manufacturer who is required to certify under paragraphs (b) through (e) 
of this section fails to obtain a certificate of conformity.

       Table 1 to Sec. 1060.5--Summary of Engine Manufacturer Evaporative Certification Responsibilities
----------------------------------------------------------------------------------------------------------------
                                             Is the engine manufacturer
                                              required to certify for       Code of Federal Regulations Cite for
             Equipment type               evaporative emission standards?              Certification
                                                        \a\
----------------------------------------------------------------------------------------------------------------
Marine SI...............................  No.............................
Large SI................................  Yes............................  40 CFR part 1048.
Recreational vehicles...................  No.............................
Small SI................................  No, unless engines are sold      40 CFR part 1060.
                                           with complete fuel systems.
----------------------------------------------------------------------------------------------------------------
\a\ Fuel lines and fuel tanks that are attached to or sold with engines must be covered by a certificate of
  conformity.


     Table 2 to Sec. 1060.5--Summary of Equipment Manufacturer Evaporative Certification Responsibilities
----------------------------------------------------------------------------------------------------------------
                                           Is the equipment manufacturer
             Equipment type                   required to certify for       Code of Federal Regulations Cite for
                                          evaporative emission standards?              Certification
----------------------------------------------------------------------------------------------------------------
Marine SI...............................  Yes, but only if vessel          40 CFR part 1060.\a\
                                           manufacturers install
                                           uncertified fuel lines or fuel
                                           tanks, or they intend to
                                           generate or use evaporative
                                           emission credits.
Large SI................................  Allowed but not required.......  40 CFR part 1060.
Recreational vehicles...................  Yes, even if vehicle             40 CFR part 1051.
                                           manufacturers install
                                           certified components.
Small SI................................  Yes, unless the equipment uses   40 CFR part 1060.\a\
                                           portable nonroad fuel tanks.
----------------------------------------------------------------------------------------------------------------
\a\ See the exhaust standard-setting part for provisions related to generating or using evaporative emission
  credits.


           Table 3 of Sec. 1060.5--Summary of Component Manufacturer Certification Responsibilities
----------------------------------------------------------------------------------------------------------------
                                           Is the component manufacturer
             Equipment type                required to certify fuel lines   Code of Federal Regulations Cite for
                                                  and fuel tanks?                      Certification
----------------------------------------------------------------------------------------------------------------
Marine SI...............................  Yes, including portable marine   40 CFR part 1060.
                                           fuel tanks and associated fuel
                                           lines \a\.
Large SI................................  Allowed but not required.......  40 CFR part 1060.
Recreational vehicles...................  Allowed but not required.......  40 CFR part 1060.
Small SI................................  Yes \a\........................  40 CFR part 1060.
----------------------------------------------------------------------------------------------------------------
\a\ See Sec. 1060.601 for an allowance to make contractual arrangements with engine or equipment manufacturers
  instead of certifying.


[73 FR 59298, Oct. 8, 2008, as amended at 80 FR 9115, Feb. 19, 2015]



Sec. 1060.10  How is this part organized?

    This part 1060 is divided into the following subparts:
    (a) Subpart A of this part defines the applicability of part 1060 
and gives an overview of regulatory requirements.
    (b) Subpart B of this part describes the emission standards and 
other requirements that must be met to certify

[[Page 10]]

equipment or components under this part. Note that Sec. 1060.110 
discusses certain interim requirements and compliance provisions that 
apply only for a limited time.
    (c) Subpart C of this part describes how to apply for a certificate 
of conformity.
    (d) Subpart D of this part describes the requirements related to 
verifying that products are being produced as described in an approved 
application for certification.
    (e) Subpart E of this part describes the requirements related to 
verifying that products are meeting the standards in use.
    (f) Subpart F of this part describes how to measure evaporative 
emissions.
    (g) Subpart G of this part and 40 CFR part 1068 describe 
requirements, prohibitions, and other provisions that apply to 
manufacturers, owners, operators, and all others.
    (h) Subpart H of this part describes how to certify your equipment 
or components for inclusion in an emission averaging program allowed by 
an exhaust standard-setting part.
    (i) Subpart I of this part contains definitions and other reference 
information.



Sec. 1060.15  Do any other CFR parts apply to me?

    (a) There is a separate part of the CFR that includes exhaust 
emission requirements for each particular application, as described in 
Sec. 1060.1(a). We refer to these as the exhaust standard-setting 
parts. In cases where an exhaust standard-setting part includes 
evaporative requirements, apply this part 1060 as specified in the 
exhaust standard-setting part, as follows:
    (1) The requirements in the exhaust standard-setting part may differ 
from the requirements in this part. In cases where it is not possible to 
comply with both the exhaust standard-setting part and this part, you 
must comply with the requirements in the exhaust standard-setting part. 
The exhaust standard-setting part may also allow you to deviate from the 
procedures of this part for other reasons.
    (2) The exhaust standard-setting parts may reference some sections 
of this part 1060 or may allow or require certification under this part 
1060. See the exhaust standard-setting parts to determine what 
provisions of this part 1060 apply for these equipment types.
    (b) The requirements and prohibitions of part 1068 of this chapter 
apply to everyone, including anyone who manufactures, imports, owns, 
operates, or services any of the fuel systems subject to this part 1060. 
Part 1068 of this chapter describes general provisions, including the 
following areas:
    (1) Prohibited acts and penalties for engine manufacturers, 
equipment manufacturers, and others.
    (2) Exclusions and exemptions for certain products.
    (3) Importing products.
    (4) Defect reporting and recall.
    (5) Procedures for hearings.
    (c) Other parts of this chapter apply if referenced in this part.



Sec. 1060.30  Submission of information.

    (a) This part includes various requirements to record data or other 
information. Refer to Sec. 1060.825, 40 CFR 1068.25, and the exhaust 
standard-setting part regarding recordkeeping requirements. If 
recordkeeping requirements are not specified, store these records in any 
format and on any media and keep them readily available for one year 
after you send an associated application for certification, or one year 
after you generate the data if they do not support an application for 
certification. You must promptly send us organized, written records in 
English if we ask for them. We may review them at any time.
    (b) The regulations in Sec. 1060.255 and 40 CFR 1068.101 describe 
your obligation to report truthful and complete information and the 
consequences of failing to meet this obligation. This includes 
information not related to certification.
    (c) Send all reports and requests for approval to the Designated 
Compliance Officer (see Sec. 1060.801).
    (d) Any written information we require you to send to or receive 
from another company is deemed to be a required record under this 
section. Such records are also deemed to be submissions to EPA. We may 
require you to send us these records whether or not you are a 
certificate holder.

[[Page 11]]



          Subpart B_Emission Standards and Related Requirements



Sec. 1060.101  What evaporative emission requirements apply under
this part?

    Products subject to this part must meet emission standards and 
related requirements as follows:
    (a) Section 1060.102 describes permeation emission control 
requirements for fuel lines.
    (b) Section 1060.103 describes permeation emission control 
requirements for fuel tanks.
    (c) Section 1060.104 describes running loss emission control 
requirements for fuel systems.
    (d) Section 1060.105 describes diurnal emission control requirements 
for fuel tanks.
    (e) The following general requirements apply for components and 
equipment subject to the emission standards in Sec. Sec. 1060.102 
through 1060.105:
    (1) Adjustable parameters. Components or equipment with adjustable 
parameters must meet all the requirements of this part for any 
adjustment in the physically adjustable range.
    (2) Prohibited controls. The following controls are prohibited:
    (i) For anyone to design, manufacture, or install emission control 
systems so they cause or contribute to an unreasonable risk to public 
health, welfare, or safety while operating.
    (ii) For anyone to design, manufacture, or install emission control 
systems with features that disable, deactivate, or bypass the emission 
controls, either actively or passively. For example, you may not include 
a manual vent that the operator can open to bypass emission controls. 
You may ask us to allow such features if needed for safety reasons or if 
the features are fully functional during emission tests described in 
subpart F of this part.
    (3) Emission credits. Equipment manufacturers are allowed to comply 
with the emission standards in this part using evaporative emission 
credits only if the exhaust standard-setting part explicitly allows it 
for evaporative emissions. See the exhaust standard-setting part and 
subpart H of this part for information about complying with evaporative 
emission credits. For equipment manufacturers to generate or use 
evaporative emission credits, components must be certified to a family 
emission limit, which serves as the standard for those components.
    (f) This paragraph (f) specifies requirements that apply to 
equipment manufacturers subject to requirements under this part, whether 
or not they are subject to and certify to any of the emission standards 
in Sec. Sec. 1060.102 through 1060.105. Equipment manufacturers meeting 
these requirements will be deemed to be certified as in conformity with 
the requirements of this paragraph (f) without submitting an application 
for certification, as follows:
    (1) Fuel caps, vents, and carbon canisters. You are responsible for 
ensuring that proper caps and vents are installed on each new piece of 
equipment that is subject to emission standards under this part. The 
following particular requirements apply to equipment that is subject to 
running loss or diurnal emission standards, including portable marine 
fuel tanks:
    (i) All equipment must have a tethered fuel cap. Fuel caps must also 
include a visual, audible, or other physical indication that they have 
been properly sealed.
    (ii) You may not add vents unless they are specified in or allowed 
by the applicable certificates of conformity.
    (iii) If the emission controls rely on carbon canisters, they must 
be installed in a way that prevents exposing the carbon to water or 
liquid fuel.
    (2) Fuel-line fittings. The following requirements apply for fuel-
line fittings that will be used with fuel lines that must meet 
permeation emission standards:
    (i) Use good engineering judgment to ensure that all fuel-line 
fittings will remain securely connected to prevent fuel leakage 
throughout the useful life of the equipment.
    (ii) Fuel lines that are intended to be detachable (such as those 
for portable marine fuel tanks) must be self-sealing when detached from 
the fuel tank or engine.
    (3) Refueling. For any equipment using fuel tanks that are subject 
to diurnal or permeation emission standards under this part, you must 
design

[[Page 12]]

and build your equipment such that operators can reasonably be expected 
to fill the fuel tank without spitback or spillage during the refueling 
event. The following examples illustrate designs that meet this 
requirement:
    (i) Equipment that is commonly refueled using a portable gasoline 
container should have a fuel tank inlet that is larger than a typical 
dispensing spout. The fuel tank inlet should be located so the operator 
can place the nozzle directly in the fuel tank inlet and see the fuel 
level in the tank while pouring the fuel from an appropriately sized 
refueling container (either through the tank wall or the fuel tank 
inlet). We will deem you to comply with the requirements of this 
paragraph (f)(3)(i) if you design your equipment to meet applicable 
industry standards related to fuel tank inlets.
    (ii) Marine SI vessels with a filler neck extending to the side of 
the boat should be designed for automatic fuel shutoff. Alternatively, 
the filler neck should be designed such that the orientation of the 
filler neck allows dispensed fuel that collects in the filler neck to 
flow back into the fuel tank. A filler neck that ends with a horizontal 
or nearly horizontal segment at the opening where fuel is dispensed 
would not be an acceptable design.
    (g) Components and equipment must meet the standards specified in 
this part throughout the applicable useful life. Where we do not specify 
procedures for demonstrating the durability of emission controls, use 
good engineering judgment to ensure that your products will meet the 
standards throughout the useful life. The useful life is one of the 
following values:
    (1) The useful life in years specified for the components or 
equipment in the exhaust standard-setting part.
    (2) The useful life in years specified for the engine in the exhaust 
standard-setting part if the exhaust standards are specified for the 
engine rather than the equipment and there is no useful life given for 
components or equipment.
    (3) Five years if no useful life is specified in years for the 
components, equipment, or engines in the exhaust standard-setting part.



Sec. 1060.102  What permeation emission control requirements apply
for fuel lines?

    (a) Nonmetal fuel lines must meet permeation requirements as 
follows:
    (1) Marine SI fuel lines, including fuel lines associated with 
outboard engines or portable marine fuel tanks, must meet the permeation 
requirements in this section.
    (2) Large SI fuel lines must meet the permeation requirements 
specified in 40 CFR 1048.105.
    (3) Fuel lines for recreational vehicles must meet the permeation 
requirements specified in 40 CFR 1051.110 or in this section.
    (4) Small SI fuel lines must meet the permeation requirements in 
this section, unless they are installed in equipment certified to meet 
diurnal emission standards under Sec. 1060.105(e).
    (b) Different categories of nonroad equipment are subject to 
different requirements with respect to fuel line permeation. Fuel lines 
are classified based on measured emissions over the test procedure 
specified for the class.
    (c) The regulations in 40 CFR part 1048 require that fuel lines used 
with Large SI engines must meet the standards for EPA Low-Emission Fuel 
Lines. The regulations in 40 CFR part 1054 require that fuel lines used 
with handheld Small SI engines installed in cold-weather equipment must 
meet the standards for EPA Cold-Weather Fuel Lines. Unless specified 
otherwise in this subchapter U, fuel lines used with all other engines 
and equipment subject to the provisions of this part 1060, including 
fuel lines associated with outboard engines or portable marine fuel 
tanks, must meet the standards for EPA Nonroad Fuel Lines.
    (d) The following standards apply for each fuel line classification:
    (1) EPA Low-Emission Fuel Lines must have permeation emissions at or 
below 10 g/m\2\/day when measured according to the test procedure 
described in Sec. 1060.510. Fuel lines that comply with this emission 
standard are deemed to comply with all the emission standards specified 
in this section.
    (2) EPA Nonroad Fuel Lines must have permeation emissions at or 
below 15 g/m\2\/day when measured according

[[Page 13]]

to the test procedure described in Sec. 1060.515.
    (3) EPA Cold-Weather Fuel Lines must meet the following permeation 
emission standards when measured according to the test procedure 
described in Sec. 1060.515:

  Table 1 to Sec. 1060.102--Permeation Standards for EPA Cold-Weather
                               Fuel Lines
------------------------------------------------------------------------
                                                           Standard (g/
                       Model year                            m\2\/day)
------------------------------------------------------------------------
2012....................................................             290
2013....................................................             275
2014....................................................             260
2015....................................................             245
2016 and later..........................................             225
------------------------------------------------------------------------

    (e) You may certify fuel lines as follow:
    (1) You may certify straight-run fuel lines as sections of any 
length.
    (2) You may certify molded fuel lines in any configuration 
representing your actual production, subject to the provisions for 
selecting a worst-case configuration in Sec. 1060.235(b).
    (3) You may certify fuel line assemblies as aggregated systems that 
include multiple sections of fuel line with connectors and fittings. For 
example, you may certify fuel lines for portable marine fuel tanks as 
assemblies of fuel hose, primer bulbs, and self-sealing end connections. 
The length of such an assembly must not be longer than a typical in-use 
installation and must always be less than 2.5 meters long. You may also 
certify primer bulbs separately. The standard applies with respect to 
the total permeation emissions divided by the wetted internal surface 
area of the assembly. Where it is not practical to determine the actual 
internal surface area of the assembly, you may assume that the internal 
surface area per unit length of the assembly is equal to the ratio of 
internal surface area per unit length of the hose section of the 
assembly.

[73 FR 59298, Oct. 8, 2008, as amended at 74 FR 8426, Feb. 24, 2009]



Sec. 1060.103  What permeation emission control requirements apply
for fuel tanks?

    (a) Fuel tanks must meet permeation requirements as follows:
    (1) Marine SI fuel tanks, including engine-mounted fuel tanks and 
portable marine fuel tanks, must meet the permeation requirements in 
this section.
    (2) Large SI fuel tanks must meet diurnal emission standards as 
specified in Sec. 1060.105, which includes measurement of permeation 
emissions. No separate permeation standard applies.
    (3) Fuel tanks for recreational vehicles must meet the permeation 
requirements specified in 40 CFR 1051.110 or in this section.
    (4) Small SI fuel tanks must meet the permeation requirements in 
this section unless they are installed in equipment certified to meet 
diurnal emission standards under Sec. 1060.105(e).
    (b) Permeation emissions from fuel tanks may not exceed 1.5 g/m\2\/
day when measured at a nominal temperature of 28  deg.C with the test 
procedures for tank permeation in Sec. 1060.520. You may also choose to 
meet a standard of 2.5 g/m\2\/day if you perform testing at a nominal 
temperature of 40  deg.C under Sec. 1060.520(d).
    (c) The exhaust standard-setting part may allow for certification of 
fuel tanks to a family emission limit for calculating evaporative 
emission credits as described in subpart H of this part instead of 
meeting the emission standards in this section.
    (d) For purposes of this part, fuel tanks do not include fuel lines 
that are subject to Sec. 1060.102, petcocks designed for draining fuel, 
grommets used with fuel lines, or grommets used with other hose or 
tubing excluded from the definition of ``fuel line.'' Fuel tanks include 
other fittings (such as fuel caps, gaskets, and O-rings) that are 
directly mounted to the fuel tank.
    (e) Fuel caps may be certified separately relative to the permeation 
emission standard in paragraph (b) of this section using the test 
procedures specified in Sec. 1060.521. Fuel caps certified alone do not 
need to meet the emission standard. Rather, fuel caps would be certified 
with a Family Emission Limit, which is used for demonstrating that fuel 
tanks meet the emission standard as described in Sec. 1060.520(b)(5). 
For the purposes of this paragraph (e), gaskets or O-rings that are 
produced as part of an assembly with the fuel cap are considered part of 
the fuel cap.

[[Page 14]]

    (f) Metal fuel tanks that meet the permeation criteria in Sec. 
1060.240(d)(2) or use certified nonmetal fuel caps will be deemed to be 
certified as in conformity with the requirements of this section without 
submitting an application for certification.

[73 FR 59298, Oct. 8, 2008, as amended at 74 FR 8427, Feb. 24, 2009; 75 
FR 23026, Apr. 30, 2010]



Sec. 1060.104  What running loss emission control requirements apply?

    (a) Engines and equipment must meet running loss requirements as 
follows:
    (1) Marine SI engines and vessels are not subject to running loss 
emission standards.
    (2) Large SI engines and equipment must prevent fuel boiling during 
operation as specified in 40 CFR 1048.105.
    (3) Recreational vehicles are not subject to running loss emission 
standards.
    (4) Nonhandheld Small SI engines and equipment that are not used in 
wintertime equipment must meet running loss requirements described in 
this section. Handheld Small SI engines and equipment are not subject to 
running loss emission standards.
    (b) You must demonstrate control of running loss emissions in one of 
the following ways if your engines or equipment are subject to the 
requirements of this section:
    (1) Route running loss emissions into the engine intake system so 
fuel vapors vented from the tank during engine operation are combusted 
in the engine. This may involve routing vapors through a carbon 
canister. If another company has certified the engine with respect to 
exhaust emissions, state in your application for certification that you 
have followed the engine manufacturer's installation instructions.
    (2) Use a fuel tank that remains sealed under normal operating 
conditions. This may involve a bladder or other means to prevent 
pressurized fuel tanks.
    (3) Get an approved Executive Order from the California Air 
Resources Board showing that your system meets applicable running loss 
standards in California.
    (c) If you are subject to both running loss and diurnal emission 
standards, use good engineering judgment to ensure that the emission 
controls are compatible.



Sec. 1060.105  What diurnal requirements apply for equipment?

    (a) Fuel tanks must meet diurnal emission requirements as follows:
    (1) Marine SI fuel tanks, including engine-mounted fuel tanks and 
portable marine fuel tanks, must meet the requirements related to 
diurnal emissions specified in this section.
    (2) Large SI fuel tanks must meet the requirements related to 
diurnal emissions specified in 40 CFR 1048.105.
    (3) Recreational vehicles are not subject to diurnal emission 
standards.
    (4) Small SI fuel tanks are not subject to diurnal emission 
standards, except as specified in paragraph (e) of this section.
    (b) Diurnal emissions from Marine SI fuel tanks may not exceed 0.40 
g/gal/day when measured using the test procedures specified in Sec. 
1060.525 for general fuel temperatures. An alternative standard of 0.16 
g/gal/day applies for fuel tanks installed in nontrailerable boats when 
measured using the corresponding fuel temperature profile in Sec. 
1060.525. Portable marine fuel tanks are not subject to the requirements 
of this paragraph (b), but must instead comply with the requirements of 
paragraphs (c) and (d) of this section.
    (c) Portable marine fuel tanks and associated fuel-system components 
must meet the following requirements:
    (1) They must be self-sealing when detached from the engines. The 
tanks may not vent to the atmosphere when attached to an engine. An 
integrated or external manually activated device may be included in the 
fuel tank design to temporarily relieve pressure before refueling or 
connecting the fuel tank to the engine. However, the default setting for 
such a vent must be consistent with the requirement in paragraph (c)(2) 
of this section.
    (2) They must remain sealed up to a positive pressure of 24.5 kPa 
(3.5 psig); however, they may contain air inlets that open when there is 
a vacuum pressure inside the tank. Such fuel tanks may not contain air 
outlets that vent to the atmosphere at pressures below 34.5 kPa (5.0 
psig).

[[Page 15]]

    (d) Detachable fuel lines that are intended for use with portable 
marine fuel tanks must have connection points that are self-sealing when 
not attached to the engine or fuel tank.
    (e) Manufacturers of nonhandheld Small SI equipment may optionally 
meet the diurnal emission standards adopted by the California Air 
Resources Board in the Final Regulation Order, Article 1, Chapter 15, 
Division 3, Title 13, California Code of Regulations, July 26, 2004 
(incorporated by reference in Sec. 1060.810). To meet this requirement, 
equipment must be certified to the performance standards specified in 
Title 13 CCR Sec. 2754(a) based on the applicable requirements 
specified in CP-902 and TP-902, including the requirements related to 
fuel caps in Title 13 CCR Sec. 2756. Equipment certified under this 
paragraph (e) does not need to use fuel lines or fuel tanks that have 
been certified separately. Equipment certified under this paragraph (e) 
are subject to all the referenced requirements as if these 
specifications were mandatory.
    (f) The following general provisions apply for controlling diurnal 
emissions:
    (1) If you are subject to both running loss and diurnal emission 
standards, use good engineering judgment to ensure that the emission 
controls are compatible.
    (2) You may not use diurnal emission controls that increase the 
occurrence of fuel spitback or spillage during in-use refueling. Also, 
if you use a carbon canister, you must incorporate design features that 
prevent liquid gasoline from reaching the canister during refueling or 
as a result of fuel sloshing or fuel expansion.
    (3) You must meet the following provisions from ABYC H-25, July 2010 
(incorporated by reference in Sec. 1060.810) with respect to portable 
marine fuel tanks:
    (i) Provide information related to the pressure relief method 
(25.8.2.1 and 25.8.2.1.1).
    (ii) Perform system testing (25.10 through 25.10.5).

[73 FR 59298, Oct. 8, 2008, as amended at 74 FR 8427, Feb. 24, 2009; 75 
FR 56482, Sept. 16, 2010]



Sec. 1060.120  What emission-related warranty requirements apply?

    (a) General requirements. The certifying manufacturer must warrant 
to the ultimate purchaser and each subsequent purchaser that the new 
nonroad equipment, including its evaporative emission control system, 
meets two conditions:
    (1) It is designed, built, and equipped so it conforms at the time 
of sale to the ultimate purchaser with the requirements of this part.
    (2) It is free from defects in materials and workmanship that may 
keep it from meeting these requirements.
    (b) Warranty period. Your emission-related warranty must be valid 
for at least two years from the point of first retail sale.
    (c) Components covered. The emission-related warranty covers all 
components whose failure would increase the evaporative emissions, 
including those listed in 40 CFR part 1068, Appendix I, and those from 
any other system you develop to control emissions. Your emission-related 
warranty does not cover components whose failure would not increase 
evaporative emissions.
    (d) Relationships between manufacturers. (1) The emission-related 
warranty required for equipment manufacturers that certify equipment 
must cover all specified components even if another company produces the 
component.
    (2) Where an equipment manufacturer fulfills a warranty obligation 
for a given component, the component manufacturer is deemed to have also 
met that obligation.



Sec. 1060.125  What maintenance instructions must I give to buyers?

    Give ultimate purchasers written instructions for properly 
maintaining and using the emission control system. You may not specify 
any maintenance more frequently than once per year. For example, if you 
produce cold-weather equipment that requires replacement of fuel cap 
gaskets or O-rings, provide clear instructions to the ultimate 
purchaser, including the required replacement interval.

[[Page 16]]



Sec. 1060.130  What installation instructions must I give to equipment
manufacturers?

    (a) If you sell a certified fuel-system component for someone else 
to install in equipment, give the installer instructions for installing 
it consistent with the requirements of this part.
    (b) Make sure the instructions have the following information:
    (1) Include the heading: ``Emission-related installation 
instructions''.
    (2) State: ``Failing to follow these instructions when installing 
[IDENTIFY COMPONENT(S)] in a piece of nonroad equipment violates federal 
law (40 CFR 1068.105(b)), subject to fines or other penalties as 
described in the Clean Air Act.''
    (3) Describe any limits on the range of applications needed to 
ensure that the component operates consistently with your application 
for certification. For example:
    (i) For fuel tanks sold without fuel caps, you must specify the 
requirements for the fuel cap, such as the allowable materials, thread 
pattern, how it must seal, etc. You must also include instructions to 
tether the fuel cap as described in Sec. 1060.101(f)(1) if you do not 
sell your fuel tanks with tethered fuel caps.
    (ii) If your fuel lines do not meet permeation standards specified 
in Sec. 1060.102 for EPA Low-Emission Fuel Lines, tell equipment 
manufacturers not to install the fuel lines with Large SI engines that 
operate on gasoline or another volatile liquid fuel.
    (4) Describe instructions for installing components so they will 
operate according to design specifications in your application for 
certification. Specify sufficient detail to ensure that the equipment 
will meet the applicable standards when your component is installed.
    (5) If you certify a component with a family emission limit above 
the emission standard, be sure to indicate that the equipment 
manufacturer must have a source of credits to offset the higher 
emissions. Also indicate the applications for which the regulations 
allow for compliance using evaporative emission credits.
    (6) Instruct the equipment manufacturers that they must comply with 
the requirements of Sec. 1060.202.
    (c) You do not need installation instructions for components you 
install in your own equipment.
    (d) Provide instructions in writing or in an equivalent format. For 
example, you may post instructions on a publicly available Web site for 
downloading or printing, provided you keep a copy of these instructions 
in your records. If you do not provide the instructions in writing, 
explain in your application for certification how you will ensure that 
each installer is informed of the installation requirements.



Sec. 1060.135  How must I label and identify the engines and equipment
I produce?

    The labeling requirements of this section apply for all equipment 
manufacturers and for engine manufacturers that certify with respect to 
evaporative emissions. See Sec. 1060.137 for the labeling requirements 
that apply separately for fuel lines, fuel tanks, and other fuel-system 
components.
    (a) You must affix a permanent and legible label identifying each 
engine or piece of equipment before introducing it into U.S. commerce. 
The label must be--
    (1) Attached in one piece so it is not removable without being 
destroyed or defaced.
    (2) Secured to a part of the engine or equipment needed for normal 
operation and not normally requiring replacement.
    (3) Durable and readable for the equipment's entire life.
    (4) Written in English.
    (5) Readily visible in the final installation. It may be under a 
hinged door or other readily opened cover. It may not be hidden by any 
cover attached with screws or any similar designs. Labels on marine 
vessels (except personal watercraft) must be visible from the helm.
    (b) If you hold a certificate for your engine or equipment with 
respect to evaporative emissions, the engine or equipment label 
specified in paragraph (a) of this section must--

[[Page 17]]

    (1) Include the heading ``EMISSION CONTROL INFORMATION''.
    (2) Include your corporate name and trademark. You may identify 
another company and use its trademark instead of yours if you comply 
with the provisions of Sec. 1060.640.
    (3) State the date of manufacture [MONTH and YEAR] of the equipment; 
however, you may omit this from the label if you stamp or engrave it on 
the equipment.
    (4) State: ``THIS EQUIPMENT [or VEHICLE or BOAT] MEETS U.S. EPA EVAP 
STANDARDS.''
    (5) Identify the certified fuel-system components installed on the 
equipment as described in this paragraph (b)(5). Establish a component 
code for each certified fuel-system component, including those certified 
by other companies. You may use part numbers, certification numbers, or 
any other unique code that you or the certifying component manufacturer 
establish. This identifying information must correspond to printing or 
other labeling on each certified fuel-system component, whether you or 
the component manufacturer certifies the individual component. You may 
identify multiple part numbers if your equipment design might include an 
option to use more than one component design (such as from multiple 
component manufacturers). Use one of the following methods to include 
information on the label that identifies certified fuel-system 
components:
    (i) Use the component codes to identify each certified fuel-system 
component on the label specified in this paragraph (b).
    (ii) Identify the emission family on the label using EPA's 
standardized designation or an abbreviated equipment code that you 
establish in your application for certification. Equipment manufacturers 
that also certify their engines with respect to exhaust emissions may 
use the same emission family name for both exhaust and evaporative 
emissions. If you use the provisions of this paragraph (b)(5)(ii), you 
must identify all the certified fuel-system components and the 
associated component codes in your application for certification. In 
this case the label specified in this paragraph (b) may omit the 
information related to specific fuel-system components.
    (c) If you produce equipment without certifying with respect to 
evaporative emissions, the equipment label specified in paragraph (a) of 
this section must--
    (1) State: ``MEETS U.S. EPA EVAP STANDARDS USING CERTIFIED 
COMPONENTS.''
    (2) Include your corporate name.
    (d) You may add information to the emission control information 
label as follows:
    (1) You may identify other emission standards that the engine meets 
or does not meet (such as California standards). You may include this 
information by adding it to the statement we specify or by including a 
separate statement.
    (2) You may add other information to ensure that the engine will be 
properly maintained and used.
    (3) You may add appropriate features to prevent counterfeit labels. 
For example, you may include the engine's unique identification number 
on the label.
    (e) Anyone subject to the labeling requirements in this part 1060 
may ask us to approve modified labeling requirements if it is necessary 
or appropriate. We will approve the request if the alternate label is 
consistent with the requirements of this part.

[73 FR 59298, Oct. 8, 2008, as amended at 75 FR 23026, Apr. 30, 2010]



Sec. 1060.137  How must I label and identify the fuel-system
components I produce?

    The requirements of this section apply for manufacturers of fuel-
system components subject to emission standards under this part 1060. 
However, these requirements do not apply if you produce fuel-system 
components that will be covered by a certificate of conformity from 
another company under Sec. 1060.601(f). These requirements also do not 
apply for components you certify if you also certify the equipment in 
which the component is installed and meet the labeling requirements in 
Sec. 1060.135.

[[Page 18]]

    (a) Label the components identified in this paragraph (a), unless 
the components are too small to be properly labeled. Unless we approve 
otherwise, we consider parts large enough to be properly labeled if they 
have space for 12 characters in six-point font (approximately 2 mm x 12 
mm). For these small parts, you may omit the label as long as you 
identify those part numbers in your maintenance and installation 
instructions.
    (1) All fuel tanks, except for metal fuel tanks that are deemed 
certified under Sec. 1060.103(f).
    (2) Fuel lines. This includes primer bulbs unless they are excluded 
from the definition of ``fuel line'' under the standard-setting part. 
Label primer bulbs separately.
    (3) Carbon canisters.
    (4) Fuel caps, as described in this paragraph (a)(4). Fuel caps must 
be labeled if they are separately certified under Sec. 1060.103 or if 
the diurnal control system requires that the fuel tank hold pressure. 
Fuel caps must also be labeled if they are mounted directly on the fuel 
tank, unless the fuel tank is certified based on a worst-case fuel cap.
    (5) Replaceable pressure-relief assemblies. This does not apply if 
the component is integral to the fuel tank or fuel cap.
    (6) Other components we determine to be critical to the proper 
functioning of evaporative emission controls.
    (b) Label your certified fuel-system components at the time of 
manufacture. The label must be--
    (1) Attached so it is not removable without being destroyed or 
defaced. This may involve printing directly on the product. For molded 
products, you may use the mold to apply the label.
    (2) Durable and readable for the equipment's entire life.
    (3) Written in English.
    (c) Except as specified in paragraph (d) of this section, you must 
create the label specified in paragraph (b) of this section as follows:
    (1) Include your corporate name. You may identify another company 
instead of yours if you comply with the provisions of Sec. 1054.640.
    (2) Include EPA's standardized designation for the emission family.
    (3) State: ``EPA COMPLIANT''.
    (4) Fuel tank labels must identify the FEL, if applicable.
    (5) Fuel line labels must identify the applicable permeation level. 
This may involve any of the following approaches:
    (i) Identify the applicable numerical emission standard (such as 15 
g/m \2\/day).
    (ii) Identify the applicable emission standards using EPA 
classifications (such as EPA Nonroad Fuel Lines).
    (iii) Identify the applicable industry standard specification (such 
as SAE J30 R12).
    (6) Fuel line labels must be continuous, with no more than 12 inches 
before repeating. We will consider labels to be continuous if the space 
between repeating segments is no longer than that of the repeated 
information. You may add a continuous stripe or other pattern to help 
identify the particular type or grade of your products.
    (d) You may create an abbreviated label for your components. Such a 
label may rely on codes to identify the component. The code must at a 
minimum identify the certification status, your corporate name, and the 
emission family. For example, XYZ Manufacturing may label its fuel lines 
as ``EPA-XYZ-A15'' to designate that their ``A15'' family was certified 
to meet EPA's 15 g/m \2\/day standard. If you do this, you must describe 
the abbreviated label in your application for certification and identify 
all the associated information specified in paragraph (c) of this 
section.
    (e) You may ask us to approve modified labeling requirements in this 
section as described in Sec. 1060.135(e).

[73 FR 59298, Oct. 8, 2008, as amended at 75 FR 23026, Apr. 30, 2010]



                 Subpart C_Certifying Emission Families



Sec. 1060.201  What are the general requirements for obtaining
a certificate of conformity?

    Manufacturers of engines, equipment, or fuel-system components may 
need to certify their products with respect to evaporative emission 
standards as described in Sec. Sec. 1060.1 and 1060.601. See Sec. 
1060.202 for requirements related to

[[Page 19]]

certifying with respect to the requirements specified in Sec. 
1060.101(f). The following general requirements apply for obtaining a 
certificate of conformity:
    (a) You must send us a separate application for a certificate of 
conformity for each emission family. A certificate of conformity for 
equipment is valid starting with the indicated effective date but it is 
not valid for any production after December 31 of the model year for 
which it is issued. No certificate will be issued after December 31 of 
the model year. A certificate of conformity for a component is valid 
starting with the indicated effective date but it is not valid for any 
production after the end of the production period for which it is 
issued.
    (b) The application must contain all the information required by 
this part and must not include false or incomplete statements or 
information (see Sec. 1060.255).
    (c) We may ask you to include less information than we specify in 
this subpart as long as you maintain all the information required by 
Sec. 1060.250. For example, equipment manufacturers might use only 
components that are certified by other companies to meet applicable 
emission standards, in which case we would not require submission of 
emission data already submitted by the component manufacturer.
    (d) You must use good engineering judgment for all decisions related 
to your application (see 40 CFR 1068.5).
    (e) An authorized representative of your company must approve and 
sign the application.
    (f) See Sec. 1060.255 for provisions describing how we will process 
your application.
    (g) We may specify streamlined procedures for small-volume equipment 
manufacturers.



Sec. 1060.202  What are the certification requirements related to
the general standards in Sec. 1060.101?

    Equipment manufacturers must ensure that their equipment is 
certified with respect to the general standards specified in Sec. 
1060.101(f) as follows:
    (a) If Sec. 1060.5 requires you to certify your equipment to any of 
the emission standards specified in Sec. Sec. 1060.102 through 
1060.105, describe in your application for certification how you will 
meet the general standards specified in Sec. 1060.101(f).
    (b) If Sec. 1060.5 does not require you to certify your equipment 
to any of the emission standards specified in Sec. Sec. 1060.102 
through 1060.105, your equipment is deemed to be certified with respect 
to the general standards specified in Sec. 1060.101(f) if you design 
and produce your equipment to meet those standards.
    (1) You must keep records as described in Sec. 1060.210. The other 
provisions of this part for certificate holders apply only as specified 
in Sec. 1060.5.
    (2) Your equipment is deemed to be certified only to the extent that 
it meets the general standards in Sec. 1060.101(f). Thus, it is a 
violation of 40 CFR 1068.101(a)(1) to introduce into U.S. commerce such 
equipment that does not meet applicable requirements under Sec. 
1060.101(f).
    (c) Instead of relying on paragraph (b) of this section, you may 
submit an application for certification and obtain a certificate from 
us. The provisions of this part apply in the same manner for 
certificates issued under this paragraph (c) as for any other 
certificate issued under this part.



Sec. 1060.205  What must I include in my application?

    This section specifies the information that must be in your 
application, unless we ask you to include less information under Sec. 
1060.201(c). We may require you to provide additional information to 
evaluate your application.
    (a) Describe the emission family's specifications and other basic 
parameters of the emission controls. Describe how you meet the running 
loss emission control requirements in Sec. 1060.104, if applicable. 
Describe how you meet any applicable equipment-based requirements of 
Sec. 1060.101(e) and (f). State whether you are requesting 
certification for gasoline or some other fuel type. List each 
distinguishable configuration in the emission family.
    (b) Describe the products you selected for testing and the reasons 
for selecting them.
    (c) Describe the test equipment and procedures that you used, 
including

[[Page 20]]

any special or alternate test procedures you used (see Sec. 1060.501).
    (d) List the specifications of the test fuel to show that it falls 
within the required ranges specified in subpart F of this part.
    (e) State the equipment applications to which your certification is 
limited. For example, if your fuel system meets the emission 
requirements of this part applicable only to handheld Small SI 
equipment, state that the requested certificate would apply only for 
handheld Small SI equipment.
    (f) Identify the emission family's useful life.
    (g) Include the maintenance instructions you will give to the 
ultimate purchaser of each new nonroad engine (see Sec. 1060.125).
    (h) Include the emission-related installation instructions you will 
provide if someone else will install your component in a piece of 
nonroad equipment (see Sec. 1060.130).
    (i) Describe your emission control information label (see Sec. Sec. 
1060.135 and 1060.137).
    (j) Identify the emission standards or FELs to which you are 
certifying the emission family.
    (k) Present emission data to show your products meet the applicable 
emission standards. Note that Sec. Sec. 1060.235 and 1060.240 allow you 
to submit an application in certain cases without new emission data.
    (l) State that your product was tested as described in the 
application (including the test procedures, test parameters, and test 
fuels) to show you meet the requirements of this part. If you did not do 
the testing, identify the source of the data.
    (m) Report all test results, including those from invalid tests, 
whether or not they were conducted according to the test procedures of 
subpart F of this part. We may ask you to send other information to 
confirm that your tests were valid under the requirements of this part.
    (n) Unconditionally certify that all the products in the emission 
family comply with the requirements of this part, other referenced parts 
of the CFR, and the Clean Air Act.
    (o) Include good-faith estimates of U.S.-directed production 
volumes. Include a justification for the estimated production volumes if 
they are substantially different than actual production volumes in 
earlier years for similar models.
    (p) Include other applicable information, such as information 
required by other subparts of this part.
    (q) Name an agent for service located in the United States. Service 
on this agent constitutes service on you or any of your officers or 
employees for any action by EPA or otherwise by the United States 
related to the requirements of this part.



Sec. 1060.210  What records should equipment manufacturers keep if
they do not apply for certification?

    If you are an equipment manufacturer that does not need to obtain a 
certificate of conformity for your equipment as described in Sec. 
1060.5, you must keep the records specified in this section to document 
compliance with applicable requirements. We may review these records at 
any time. If we ask, you must send us these records within 30 days. You 
must keep these records for eight years from the end of the model year.
    (a) Identify your equipment models and the annual U.S.-directed 
production volumes for each model.
    (b) Identify the emission family names of the certificates that will 
cover your equipment, the part numbers of those certified components, 
and the names of the companies that hold the certificates. You must be 
able to identify this information for each piece of equipment you 
produce.
    (c) Describe how you comply with any emission-related installation 
instructions, labeling requirements, and the general standards in Sec. 
1060.101(e) and (f).



Sec. 1060.225  How do I amend my application for certification?

    Before we issue a certificate of conformity, you may amend your 
application to include new or modified configurations, subject to the 
provisions of this section. After we have issued your certificate of 
conformity, you may send us an amended application requesting that we 
include new or modified configurations within the scope of

[[Page 21]]

the certificate, subject to the provisions of this section. You must 
amend your application if any changes occur with respect to any 
information included in your application.
    (a) You must amend your application before you take any of the 
following actions:
    (1) Add a configuration to an emission family. In this case, the 
configuration added must be consistent with other configurations in the 
emission family with respect to the criteria listed in Sec. 1060.230.
    (2) Change a configuration already included in an emission family in 
a way that may affect emissions, or change any of the components you 
described in your application for certification. This includes 
production and design changes that may affect emissions any time during 
the equipment's lifetime.
    (3) Modify an FEL for an emission family as described in paragraph 
(f) of this section. Note however that component manufacturers may not 
modify an FEL for their products unless they submit a separate 
application for a new emission family.
    (b) To amend your application for certification, send the Designated 
Compliance Officer the following information:
    (1) Describe in detail the addition or change in the configuration 
you intend to make.
    (2) Include engineering evaluations or data showing that the amended 
emission family complies with all applicable requirements. You may do 
this by showing that the original emission data are still appropriate 
for showing that the amended family complies with all applicable 
requirements.
    (3) If the original emission data for the emission family are not 
appropriate to show compliance for the new or modified configuration, 
include new test data showing that the new or modified configuration 
meets the requirements of this part.
    (c) We may ask for more test data or engineering evaluations. Within 
30 days after we make our request, you must provide the information or 
describe your plan for providing it in a timely manner.
    (d) For emission families already covered by a certificate of 
conformity, we will determine whether the existing certificate of 
conformity covers your new or modified configuration. You may ask for a 
hearing if we deny your request (see Sec. 1060.820).
    (e) For emission families already covered by a certificate of 
conformity, you may start producing the new or modified configuration 
anytime after you send us your amended application and before we make a 
decision under paragraph (d) of this section. However, if we determine 
that the affected configurations do not meet applicable requirements, we 
will notify you to cease production of the configurations and may 
require you to recall the equipment at no expense to the owner. Choosing 
to produce equipment under this paragraph (e) is deemed to be consent to 
recall all equipment that we determine do not meet applicable emission 
standards or other requirements and to remedy the nonconformity at no 
expense to the owner. If you do not provide information we request under 
paragraph (c) of this section within 30 days after we request it, you 
must stop producing the new or modified equipment.
    (f) If you hold a certificate of conformity for equipment and you 
have certified the fuel tank that you install in the equipment, you may 
ask us to approve a change to your FEL after the start of production. 
The changed FEL may not apply to equipment you have already introduced 
into U.S. commerce, except as described in this paragraph (f). If we 
approve a changed FEL after the start of production, you must identify 
the date or serial number for applying the new FEL. If you identify this 
by month and year, we will consider that a lowered FEL applies on the 
last day of the month and a raised FEL applies on the first day of the 
month. You may ask us to approve a change to your FEL in the following 
cases:
    (1) You may ask to raise your FEL for your emission family at any 
time. In your request, you must show that you will still be able to meet 
the emission standards as specified in the exhaust standard-setting 
part. If you amend your application by submitting new test data to 
include a newly added or modified fuel tank configuration, as

[[Page 22]]

described in paragraph (b)(3) of this section, use the appropriate FELs 
with corresponding production volumes to calculate your production-
weighted average FEL for the model year. In all other circumstances, you 
must use the higher FEL for the entire family to calculate your 
production-weighted average FEL under subpart H of this part.
    (2) You may ask to lower the FEL for your emission family only if 
you have test data from production units showing that emissions are 
below the proposed lower FEL. The lower FEL applies only for units you 
produce after we approve the new FEL. Use the appropriate FELs with 
corresponding production volumes to calculate your production-weighted 
average FEL for the model year.
    (g) Component manufacturers may not change an emission family's FEL 
under any circumstances. Changing the FEL would require submission of a 
new application for certification.



Sec. 1060.230  How do I select emission families?

    (a) For purposes of certification, divide your product line into 
families of equipment (or components) that are expected to have similar 
emission characteristics throughout their useful life.
    (b) Group fuel lines into the same emission family if they are the 
same in all the following aspects:
    (1) Type of material including barrier layer.
    (2) Production method.
    (3) Types of connectors and fittings (material, approximate wall 
thickness, etc.) for fuel line assemblies certified together.
    (c) Group fuel tanks (or fuel systems including fuel tanks) into the 
same emission family if they are the same in all the following aspects:
    (1) Type of material, including any pigments, plasticizers, UV 
inhibitors, or other additives that are expected to affect control of 
emissions.
    (2) Production method.
    (3) Relevant characteristics of fuel cap design for fuel systems 
subject to diurnal emission requirements.
    (4) Gasket material.
    (5) Emission control strategy.
    (6) Family emission limit, if applicable.
    (d) Group other fuel-system components and equipment into the same 
emission family if they are the same in all the following aspects:
    (1) Emission control strategy and design.
    (2) Type of material (such as type of charcoal used in a carbon 
canister). This criteria does not apply for materials that are unrelated 
to emission control performance.
    (3) The fuel systems meet the running loss emission standard based 
on the same type of compliance demonstration specified in Sec. 
1060.104(b), if applicable.
    (e) You may subdivide a group of equipment or components that are 
identical under paragraphs (b) through (d) of this section into 
different emission families if you show the expected emission 
characteristics are different during the useful life.
    (f) In unusual circumstances, you may group equipment or components 
that are not identical with respect to the things listed in paragraph 
(b) through (d) of this section into the same emission family if you 
show that their emission characteristics during the useful life will be 
similar. The provisions of this paragraph (f) do not exempt any engines 
or equipment from meeting all the applicable standards and requirements 
in subpart B of this part.
    (g) Emission families may include components used in multiple 
equipment categories. Such families are covered by a single certificate. 
For example, a single emission family may contain fuel tanks used in 
both Small SI equipment and Marine SI vessels.



Sec. 1060.235  What emission testing must I perform for my application
for a certificate of conformity?

    This section describes the emission testing you must perform to show 
compliance with the emission standards in subpart B of this part.
    (a) Test your products using the procedures and equipment specified 
in subpart F of this part.
    (b) Select an emission-data unit from each emission family for 
testing. If you are certifying with a family emission limit, you must 
test at least three emission-data units. In general, you

[[Page 23]]

must test a preproduction product that will represent actual production. 
However, for fuel tank permeation, you may test a tank with standardized 
geometry provided that it is made of the same material(s) and 
appropriate wall thickness. In general, the test procedures specify that 
components or systems be tested rather than complete equipment. For 
example, to certify your family of Small SI equipment, you would need to 
test a sample of fuel line for permeation emissions and a fuel tank for 
permeation emissions. Note that paragraph (e) of this section and Sec. 
1060.240 allow you in certain circumstances to certify without testing 
an emission-data unit from the emission family. Select test components 
that are most likely to exceed (or have emissions nearer to) the 
applicable emission standards as follows:
    (1) For fuel tanks, consider the following factors associated with 
higher emission levels:
    (i) Smallest average wall thickness (or barrier thickness, as 
appropriate).
    (ii) Greatest extent of pinch welds for tanks using barrier 
technologies.
    (iii) Greatest relative area of gasket material, especially if 
gaskets are made of high-permeation materials.
    (2) For fuel lines, consider the following factors associated with 
higher emission levels:
    (i) Smallest average wall thickness (or barrier thickness, as 
appropriate).
    (ii) Smallest inner diameter.
    (c) You may not do maintenance on emission-data units.
    (d) We may measure emissions from any of your products from the 
emission family, as follows:
    (1) You must supply your products to us if we choose to perform 
confirmatory testing.
    (2) If we measure emissions on one of your products, the results of 
that testing become the official emission results for the emission 
family. Unless we later invalidate these data, we may decide not to 
consider your data in determining if your emission family meets 
applicable requirements.
    (e) You may ask to use carryover emission data from a previous 
production period instead of doing new tests, but only if all the 
following are true:
    (1) The emission family from the previous production period differs 
from the current emission family only with respect to production period 
or other characteristics unrelated to emissions. You may also ask to add 
a configuration subject to Sec. 1060.225.
    (2) The emission-data unit from the previous production period 
remains the appropriate emission-data unit under paragraph (b) of this 
section. For example, you may not carryover emission data for your 
family of nylon fuel tanks if you have added a thinner-walled fuel tank 
than was tested previously.
    (3) The data show that the emission-data unit would meet all the 
requirements that apply to the emission family covered by the 
application for certification.
    (f) We may require you to test another unit of the same or different 
configuration in addition to the unit(s) tested under paragraph (b) of 
this section.
    (g) If you use an alternate test procedure under Sec. 1060.505, and 
later testing shows that such testing does not produce results that are 
equivalent to the procedures specified in this part, we may reject data 
you generated using the alternate procedure.



Sec. 1060.240  How do I demonstrate that my emission family complies
with evaporative emission standards?

    (a) For purposes of certification, your emission family is 
considered in compliance with an evaporative emission standard in 
subpart B of this part if you do either of the following:
    (1) You have test results showing a certified emission level from 
the fuel tank or fuel line (as applicable) in the family are at or below 
the applicable standard.
    (2) You comply with design specifications as specified in paragraphs 
(d) through (f) of this section.
    (b) Your emission family is deemed not to comply if any fuel tank or 
fuel line representing that family has an official emission result above 
the standard.
    (c) Round each official emission result to the same number of 
decimal places as the emission standard.

[[Page 24]]

    (d) You may demonstrate for certification that your emission family 
complies with the fuel tank permeation standards specified in Sec. 
1060.103 with any of the following control technologies:
    (1) A coextruded high-density polyethylene fuel tank with a 
continuous ethylene vinyl alcohol barrier layer (with not more than 40 
molar percent ethylene) making up at least 2 percent of the fuel tank's 
overall wall thickness with any of the following gasket and fuel-cap 
characteristics:
    (i) No nonmetal gaskets or fuel caps.
    (ii) All nonmetal gaskets and fuel caps made from low-permeability 
materials.
    (iii) Nonmetal gaskets and fuel caps that are not made from low-
permeability materials up to the following limits:
    (A) Gaskets with a total exposed surface area less than 0.25 percent 
of the total inside surface area of the fuel tank. For example, a fuel 
tank with an inside surface area of 0.40 square meters may use high-
permeation gasket material representing a surface area of up to 1,000 
mm\2\ (0.25% x \1/100\ x 0.40 m\2\ x 1,000,000 mm\2\/m\2\). Determine 
surface area based on the amount of material exposed to liquid fuel.
    (B) Fuel caps directly mounted to the fuel tank with the surface 
area of the fuel cap less than 3.0 percent of the total inside surface 
area of the fuel tank. Use the smallest inside cross-sectional area of 
the opening on which the cap is mounted as the fuel cap's surface area.
    (2) A metal fuel tank with the gasket and fuel-cap characteristics 
meeting the specifications in paragraphs (d)(1)(i) through (iii) of this 
section.
    (e) You may demonstrate for certification that your emission family 
complies with the diurnal emission standards specified in Sec. 1060.105 
with any of the following control technologies:
    (1) A Marine SI fuel tank sealed up to a positive pressure of 7.0 
kPa (1.0 psig); however, the fuel tank may contain air inlets that open 
when there is a vacuum pressure inside the tank.
    (2) A Marine SI fuel tank equipped with a passively purged carbon 
canister that meets the requirements of this paragraph (e)(2). The 
carbon must adsorb no more than 0.5 grams of water per gram of carbon at 
90% relative humidity and a temperature of 25[5  deg.C. The carbon 
granules must have a minimum mean diameter of 3.1 mm based on the 
procedures in ASTM D2862 (incorporated by reference in Sec. 1060.810). 
The carbon must also pass a dust attrition test based on ASTM D3802 
(incorporated by reference in Sec. 1060.810), except that hardness is 
defined as the ratio of mean particle diameter before and after the test 
and the procedure must involve twenty \1/2\-inch steel balls and ten \3/
4\-inch steel balls. Use good engineering judgment in the structural 
design of the carbon canister. The canister must have a volume 
compensator or some other device to prevent the carbon pellets from 
moving within the canister as a result of vibration or changing 
temperature. The canister must have a minimum working capacity as 
follows:
    (i) You may use the measurement procedures specified by the 
California Air Resources Board in Attachment 1 to TP-902 to show that 
canister working capacity is least 3.6 grams of vapor storage capacity 
per gallon of nominal fuel tank capacity (or 1.4 grams of vapor storage 
capacity per gallon of nominal fuel tank capacity for fuel tanks used in 
nontrailerable boats). TP-902 is part of Final Regulation Order, Article 
1, Chapter 15, Division 3, Title 13, California Code of Regulations, 
July 26, 2004 as adopted by the California Air Resources Board 
(incorporated by reference in Sec. 1060.810).
    (ii) You may produce canisters with a minimum carbon volume of 0.040 
liters per gallon of nominal fuel tank capacity (or 0.016 liters per 
gallon for fuel tanks used in nontrailerable boats). The carbon canister 
must have a minimum effective length-to-diameter ratio of 3.5 and the 
vapor flow must be directed with the intent of using the whole carbon 
bed. The carbon must have a minimum carbon working capacity of 90 grams 
per liter.
    (f) We may establish additional design certification options where 
we find that new test data demonstrate that the use of a different 
technology design will ensure compliance with the applicable emission 
standards.

[[Page 25]]

    (g) You may not establish a family emission limit below the emission 
standard for components certified based on design specifications under 
this section even if actual emission rates are much lower.



Sec. 1060.250  What records must I keep?

    (a) Organize and maintain the following records:
    (1) A copy of all applications and any summary information you send 
us.
    (2) Any of the information we specify in Sec. 1060.205 that you 
were not required to include in your application.
    (3) A detailed history of each emission-data unit. For each emission 
data unit, include all of the following:
    (i) The emission-data unit's construction, including its origin and 
buildup, steps you took to ensure that it represents production 
equipment, any components you built specially for it, and all the 
components you include in your application for certification.
    (ii) All your emission tests, including documentation on routine and 
standard tests, and the date and purpose of each test.
    (iii) All tests to diagnose emission control performance, giving the 
date and time of each and the reasons for the test.
    (iv) Any other significant events.
    (4) Annual production figures for each emission family divided by 
assembly plant.
    (5) Keep a list of equipment identification numbers for all the 
equipment you produce under each certificate of conformity.
    (b) Keep required data from routine emission tests (such as 
temperature measurements) for one year after we issue the associated 
certificate of conformity. Keep all other information specified in 
paragraph (a) of this section for eight years after we issue your 
certificate.
    (c) Store these records in any format and on any media as long as 
you can promptly send us organized, written records in English if we ask 
for them. You must keep these records readily available. We may review 
them at any time.



Sec. 1060.255  What decisions may EPA make regarding my certificate
of conformity?

    (a) If we determine your application is complete and shows that the 
emission family meets all the requirements of this part and the Clean 
Air Act, we will issue a certificate of conformity for your emission 
family for that production period. We may make the approval subject to 
additional conditions.
    (b) We may deny your application for certification if we determine 
that your emission family fails to comply with emission standards or 
other requirements of this part or the Clean Air Act. We will base our 
decision on all available information. If we deny your application, we 
will explain why in writing.
    (c) In addition, we may deny your application or suspend or revoke 
your certificate if you do any of the following:
    (1) Refuse to comply with any testing or reporting requirements.
    (2) Submit false or incomplete information (paragraph (e) of this 
section applies if this is fraudulent).
    (3) Render inaccurate any test data.
    (4) Deny us from completing authorized activities despite our 
presenting a warrant or court order (see 40 CFR 1068.20). This includes 
a failure to provide reasonable assistance.
    (5) Produce equipment or components for importation into the United 
States at a location where local law prohibits us from carrying out 
authorized activities.
    (6) Fail to supply requested information or amend your application 
to include all equipment or components being produced.
    (7) Take any action that otherwise circumvents the intent of the 
Clean Air Act or this part.
    (d) We may void your certificate if you do not keep the records we 
require or do not give us information when we ask for it.
    (e) We may void your certificate if we find that you intentionally 
submitted false or incomplete information.
    (f) If we deny your application or suspend, revoke, or void your 
certificate, you may ask for a hearing (see Sec. 1060.820).

[[Page 26]]



                Subpart D_Production Verification Testing



Sec. 1060.301  Manufacturer testing.

    (a) Using good engineering judgment, you must evaluate production 
samples to verify that equipment or components you produce are as 
specified in the certificate of conformity. This may involve testing 
using certification procedures or other measurements.
    (b) You must give us records to document your evaluation if we ask 
for them.



Sec. 1060.310  Supplying products to EPA for testing.

    Upon our request, you must supply a reasonable number of production 
samples to us for verification testing.



                        Subpart E_In-use Testing



Sec. 1060.401  General Provisions.

    We may perform in-use testing of any equipment or fuel-system 
components subject to the standards of this part.



                        Subpart F_Test Procedures



Sec. 1060.501  General testing provisions.

    (a) This subpart is addressed to you as a certifying manufacturer 
but it applies equally to anyone who does testing for you.
    (b) Unless we specify otherwise, the terms ``procedures'' and ``test 
procedures'' in this part include all aspects of testing, including the 
equipment specifications, calibrations, calculations, and other 
protocols and procedural specifications needed to measure emissions.
    (c) The specification for gasoline to be used for testing is given 
in 40 CFR 1065.710. Use the grade of gasoline specified for general 
testing. For testing specified in this part that requires a blend of 
gasoline and ethanol, blend this grade of gasoline with fuel-grade 
ethanol meeting the specifications of ASTM D4806 (incorporated by 
reference in Sec. 1060.810). You do not need to measure the ethanol 
concentration of such blended fuels and may instead calculate the 
blended composition by assuming that the ethanol is pure and mixes 
perfectly with the base fuel. For example, if you mix 10.0 liters of 
fuel-grade ethanol with 90.0 liters of gasoline, you may assume the 
resulting mixture is 10.0 percent ethanol. You may use more or less pure 
ethanol if you can demonstrate that it will not affect your ability to 
demonstrate compliance with the applicable emission standards. Note that 
unless we specify otherwise, any references to gasoline-ethanol mixtures 
containing a specified ethanol concentration means mixtures meeting the 
provisions of this paragraph (c).
    (d) Accuracy and precision of all temperature measurements must be 
[1.0  deg.C or better. If you use multiple sensors to measure 
differences in temperature, calibrate the sensors so they will be within 
0.5  deg.C of each other when they are in thermal equilibrium at a point 
within the range of test temperatures (use the starting temperature in 
Table 1 to Sec. 1060.525 unless this is not feasible).
    (e) Accuracy and precision of mass balances must be sufficient to 
ensure accuracy and precision of two percent or better for emission 
measurements for products at the maximum level allowed by the standard. 
The readability of the display may not be coarser than half of the 
required accuracy and precision. Examples are shown in the following 
table for a digital readout:

----------------------------------------------------------------------------------------------------------------
                                              Example 1               Example 2               Example 3
----------------------------------------------------------------------------------------------------------------
Applicable standard..................  1.5 g/m\2\/day.........  1.5 g/m\2\/day.........  15 g/m\2\/day.
Internal surface area................  1.15 m\2\..............  0.47 m\2\..............  0.015 m\2\.
Length of test.......................  14.0 days..............  14.0 days..............  14.1 days.
Maximum allowable mass change........  24.15 g................  9.87 g.................  3.173 g.
Required accuracy and precision......  [0.483 g or better.....  [0.197 g or better.....  [0.0635 g or better.
Required readability.................  0.1 g or better........  0.1 g or better........  0.01 g or better.
----------------------------------------------------------------------------------------------------------------


[[Page 27]]


[73 FR 59298, Oct. 8, 2008, as amended at 74 FR 8427, Feb. 24, 2009]



Sec. 1060.505  Other procedures.

    (a) Your testing. The procedures in this part apply for all testing 
you do to show compliance with emission standards, with certain 
exceptions listed in this section.
    (b) Our testing. These procedures generally apply for testing that 
we do to determine if your equipment complies with applicable emission 
standards. We may perform other testing as allowed by the Clean Air Act.
    (c) Exceptions. We may allow or require you to use procedures other 
than those specified in this part in the following cases:
    (1) You may request to use special procedures if your equipment 
cannot be tested using the specified procedures. We will approve your 
request if we determine that it would produce emission measurements that 
represent in-use operation and we determine that it can be used to show 
compliance with the requirements of the standard-setting part.
    (2) You may ask to use emission data collected using other 
procedures, such as those of the California Air Resources Board or the 
International Organization for Standardization. We will approve this 
only if you show us that using these other procedures does not affect 
your ability to show compliance with the applicable emission standards. 
This generally requires emission levels to be far enough below the 
applicable emission standards so any test differences do not affect your 
ability to state unconditionally that your equipment will meet all 
applicable emission standards when tested using the specified test 
procedures.
    (3) You may request to use alternate procedures that are equivalent 
to allowed procedures or are more accurate or more precise than allowed 
procedures. See 40 CFR 1065.12 for a description of the information that 
is generally required to show that an alternate test procedure is 
equivalent.
    (4) The test procedures are specified for gasoline-fueled equipment. 
If your equipment will use another volatile liquid fuel instead of 
gasoline, use a test fuel that is representative of the fuel that will 
be used with the equipment in use. You may ask us to approve other 
changes to the test procedures to reflect the effects of using a fuel 
other than gasoline.
    (d) Approval. If we require you to request approval to use other 
procedures under paragraph (c) of this section, you may not use them 
until we approve your request.



Sec. 1060.510  How do I test EPA Low-Emission Fuel Lines for 
permeation emissions?

    For EPA Low-Emission Fuel Lines, measure emissions according to SAE 
J2260, which is incorporated by reference in Sec. 1060.810.

[74 FR 8427, Feb. 24, 2009]



Sec. 1060.515  How do I test EPA Nonroad Fuel Lines and EPA Cold-
Weather Fuel Lines for permeation emissions?

    Measure emission as follows for EPA Nonroad Fuel Lines and EPA Cold-
Weather Fuel Lines:
    (a) Prior to permeation testing, use good engineering judgment to 
precondition the fuel line by filling it with the fuel specified in this 
paragraph (a), sealing the openings, and soaking it for at least four 
weeks at 43 [5  deg.C or eight weeks at 23 [5  deg.C.
    (1) For EPA Nonroad Fuel Lines, use Fuel CE10, which is Fuel C as 
specified in ASTM D471 (incorporated by reference in Sec. 1060.810) 
blended with ethanol such that the blended fuel has 10.0 [1.0 percent 
ethanol by volume.
    (2) For EPA Cold-Weather Fuel Lines, use gasoline blended with 
ethanol such that the blended fuel has 10.0 [1.0 percent ethanol by 
volume.
    (b) Drain the fuel line and refill it immediately with the fuel 
specified in paragraph (a) of this section. Be careful not to spill any 
fuel.
    (c) Except as specified in paragraph (d) of this section, measure 
fuel line permeation emissions using the equipment and procedures for 
weight-loss testing specified in SAE J30 or SAE J1527 (incorporated by 
reference in Sec. 1060.810). Start the measurement procedure within 8 
hours after draining and refilling the fuel line. Perform the emission 
test over a sampling period of 14 days. You may omit up to two daily

[[Page 28]]

measurements in any seven day period. Determine your final emission 
result based on the average of measured values over the 14-day period. 
Maintain an ambient temperature of 23[2  deg.C throughout the sampling 
period.
    (d) For fuel lines with a nominal inner diameter below 5.0 mm, you 
may alternatively measure fuel line permeation emissions using the 
equipment and procedures for weight-loss testing specified in SAE J2996 
(incorporated by reference in Sec. 1060.810). Determine your final 
emission result based on the average of measured values over the 14-day 
sampling period. Maintain an ambient temperature of 23[2  deg.C 
throughout the sampling period.
    (e) Use good engineering judgment to test short fuel line segments. 
For example, you may need to join individual fuel line segments using 
proper connection fittings to achieve enough length and surface area for 
a proper measurement. Size the fuel reservoir appropriately for the 
tested fuel line.

[73 FR 59298, Oct. 8, 2008, as amended at 74 FR 8427, Feb. 24, 2009; 75 
FR 23027, Apr. 30, 2010; 80 FR 9116, Feb. 19, 2015]



Sec. 1060.520  How do I test fuel tanks for permeation emissions?

    Measure permeation emissions by weighing a sealed fuel tank before 
and after a temperature-controlled soak.
    (a) Preconditioning durability testing. Take the following steps 
before an emission test, in any order, if your emission control 
technology involves surface treatment or other post-processing 
treatments such as an epoxy coating:
    (1) Pressure cycling. Perform a pressure test by sealing the tank 
and cycling it between + 13.8 and -3.4 kPa ( + 2.0 and -0.5 psig) for 
10,000 cycles at a rate of 60 seconds per cycle. The purpose of this 
test is to represent environmental wall stresses caused by pressure 
changes and other factors (such as vibration or thermal expansion). If 
your tank cannot be tested using the pressure cycles specified by this 
paragraph (a)(1), you may ask to use special test procedures under Sec. 
1060.505.
    (2) UV exposure. Perform a sunlight-exposure test by exposing the 
tank to an ultraviolet light of at least 24 W/m\2\ (0.40 W-hr/m\2\/min) 
on the tank surface for at least 450 hours. Alternatively, the fuel tank 
may be exposed to direct natural sunlight for an equivalent period of 
time as long as you ensure that the tank is exposed to at least 450 
daylight hours.
    (3) Slosh testing. Perform a slosh test by filling the tank to 40-50 
percent of its capacity with the fuel specified in paragraph (e) of this 
section and rocking it at a rate of 15 cycles per minute until you reach 
one million total cycles. Use an angle deviation of + 15 deg. to -
15 deg. from level.
    (4) Cap testing. Perform durability cycles on fuel caps intended for 
use with handheld equipment by putting the fuel cap on and taking it off 
300 times. Tighten the fuel cap each time in a way that represents the 
typical in-use experience.
    (b) Preconditioning fuel soak. Take the following steps before an 
emission test:
    (1) Fill the tank with the fuel specified in paragraph (e) of this 
section, seal it, and allow it to soak at 28 [5  deg.C for at least 20 
weeks. Alternatively, the tank may be soaked for at least 10 weeks at 
43[5  deg.C. You may count the time of the preconditioning steps in 
paragraph (a) of this section as part of the preconditioning fuel soak 
as long as the ambient temperature remains within the specified 
temperature range and the fuel tank is at least 40 percent full; you may 
add or replace fuel as needed to conduct the specified durability 
procedures.
    (2) Empty the fuel tank and immediately refill it with the specified 
test fuel to its nominal capacity. Be careful not to spill any fuel.
    (3) [Reserved]
    (4) Allow the tank and its contents to equilibrate to the 
temperatures specified in paragraph (d)(7) of this section. Seal the 
fuel tank as described in paragraph (b)(5) of this section once the fuel 
temperatures are stabilized at the test temperature. You must seal the 
tank no more than eight hours after refueling. Until the fuel tank is 
sealed, take steps to minimize the vapor losses from the fuel tank, such 
as keeping the fuel cap loose on the fuel inlet or routing vapors 
through a vent hose.
    (5) Seal the fuel tank as follows:
    (i) If fuel tanks are designed for use with a filler neck such that 
the fuel

[[Page 29]]

cap is not directly mounted on the fuel tank, you may seal the fuel 
inlet with a nonpermeable covering.
    (ii) If fuel tanks are designed with fuel caps directly mounted on 
the fuel tank, take one of the following approaches:
    (A) Use a production fuel cap expected to have permeation emissions 
at least as high as the highest-emitting fuel cap that you expect to be 
used with fuel tanks from the emission family. It would generally be 
appropriate to consider an HDPE fuel cap with a nitrile rubber seal to 
be worst-case.
    (B) You may seal the fuel inlet with a nonpermeable covering if you 
separately account for permeation emissions from the fuel cap. This may 
involve a separate measurement of permeation emissions from a worst-case 
fuel cap as described in Sec. 1060.521. This may also involve 
specifying a worst-case Family Emission Limit based on separately 
certified fuel caps as described in Sec. 1060.103(e).
    (C) If you use or specify a fuel gasket made of low-permeability 
material, you may seal the fuel inlet with a nonpermeable covering and 
calculate an emission rate for the complete fuel tank using a default 
value of 30 g/m\2\/day for the fuel cap (or 50 g/m\2\/day for testing at 
40  deg.C). Use the smallest inside cross-sectional area of the opening 
on which the cap is mounted as the fuel cap's surface area.
    (iii) Openings that are not normally sealed on the fuel tank (such 
as hose-connection fittings and vents in fuel caps) may be sealed using 
nonpermeable fittings such as metal or fluoropolymer plugs.
    (iv) Openings for petcocks that are designed for draining fuel may 
be sealed using nonpermeable fittings such as metal or fluoropolymer 
plugs.
    (v) Openings for grommets may be sealed using nonpermeable fittings 
such as metal or fluoropolymer plugs.
    (vi) Rather than sealing a fuel tank with nonpermeable fittings, you 
may produce a fuel tank for testing without machining or stamping those 
holes.
    (c) Reference tank. A reference tank is required to correct for 
buoyancy effects that may occur during testing. Prepare the reference 
tank as follows:
    (1) Obtain a second tank whose total volume is within 5 percent of 
the test tank's volume. You may not use a tank that has previously 
contained fuel or any other contents that might affect its mass 
stability.
    (2) Fill the reference tank with enough glass beads (or other inert 
material) so the mass of the reference tank is approximately the same as 
the test tank when filled with fuel. Considering the performance 
characteristics of your balance, use good engineering judgment to 
determine how similar the mass of the reference tank needs to be to the 
mass of the test tank.
    (3) Ensure that the inert material is dry.
    (4) Seal the tank.
    (d) Permeation test run. To run the test, take the following steps 
after preconditioning:
    (1) Determine the fuel tank's internal surface area in square-
meters, accurate to at least three significant figures. You may use less 
accurate estimates of the surface area if you make sure not to 
overestimate the surface area.
    (2) Weigh the sealed test tank and record the weight. Place the 
reference tank on the balance and tare it so it reads zero. Place the 
sealed test tank on the balance and record the difference between the 
test tank and the reference tank. This value is Mo. Take this 
measurement directly after sealing the test tank as specified in 
paragraphs (b)(4) and (5) of this section.
    (3) Carefully place the tank within a temperature-controlled room or 
enclosure. Do not spill or add any fuel.
    (4) Close the room or enclosure as needed to control temperatures 
and record the time. However, you may need to take steps to prevent an 
accumulation of hydrocarbon vapors in the room or enclosure that might 
affect the degree to which fuel permeates through the fuel tank. This 
might simply involve passive ventilation to allow fresh air exchanges.
    (5) Ensure that the measured temperature in the room or enclosure 
stays within the temperatures specified in paragraph (d)(6) of this 
section.
    (6) Leave the tank in the room or enclosure for the duration of the 
test run.
    (7) Hold the temperature of the room or enclosure at 28 [2  deg.C; 
measure and

[[Page 30]]

record the temperature at least daily. You may alternatively hold the 
temperature of the room or enclosure at 40 [2  deg.C to demonstrate 
compliance with the alternative standards specified in Sec. 
1060.103(b).
    (8) Measure weight loss daily by retaring the balance using the 
reference tank and weighing the sealed test tank. Calculate the 
cumulative weight loss in grams for each measurement. Calculate the 
coefficient of determination, r\2\, based on a linear plot of cumulative 
weight loss vs. test days. Use the equation in 40 CFR 1065.602(k), with 
cumulative weight loss represented by yi and cumulative time 
represented by yref. The daily measurements must be at 
approximately the same time each day. You may omit up to two daily 
measurements in any seven-day period. Test for ten full days, then 
determine when to stop testing as follows:
    (i) You may stop testing after the measurement on the tenth day if 
r\2\ is at or above 0.95 or if the measured value is less than 50 
percent of the applicable standard. (Note that if a Family Emission 
Limit applies for the family, it is considered to be the applicable 
standard for that family.) This means that if you stop testing with an 
r\2\ below 0.95, you may not use the data to show compliance with a 
Family Emission Limit less than twice the measured value.
    (ii) If after ten days of testing your r\2\ value is below 0.95 and 
your measured value is more than 50 percent of the applicable standard, 
continue testing for a total of 20 days or until r\2\ is at or above 
0.95. If r\2\ is not at or above 0.95 within 20 days of testing, 
discontinue the test and precondition the fuel tank further until it has 
stabilized emission levels, then repeat the testing.
    (9) Record the difference in mass between the reference tank and the 
test tank for each measurement. This value is Mi, where i is 
a counter representing the number of days elapsed. Subtract 
Mi from Mo and divide the difference by the 
internal surface area of the fuel tank. Divide this g/m\2\ value by the 
number of test days (using at least two decimal places) to calculate the 
emission rate in g/m\2\/day. Example: If a tank with an internal surface 
area of 0.720 m\2\ weighed 1.31 grams less than the reference tank at 
the beginning of the test and weighed 9.86 grams less than the reference 
tank after soaking for 10.03 days, the emission rate would be--

((-1.31 g)-(-9.86 g))/0.720 m\2\/10.03 days = 1.1839 g/m\2\/day
    (10) Determine your final emission result based on the cumulative 
weight loss measured on the final day of testing. Round this result to 
the same number of decimal places as the emission standard.
    (e) Fuel specifications. Use gasoline blended with ethanol such that 
the blended fuel has 10.0 [1.0 percent ethanol by volume as specified in 
Sec. 1060.501. As an alternative, you may use Fuel CE10, as described 
in Sec. 1060.515(a)(1).
    (f) Flow chart. The following figure presents a flow chart for the 
permeation testing described in this section:

[[Page 31]]

[GRAPHIC] [TIFF OMITTED] TR08OC08.078


[[Page 32]]



[73 FR 59298, Oct. 8, 2008, as amended at 75 FR 23027, Apr. 30, 2010; 80 
FR 9116, Feb. 19, 2015]



Sec. 1060.521  How do I test fuel caps for permeation emissions?

    If you measure a fuel tank's permeation emissions with a 
nonpermeable covering in place of the fuel cap under Sec. 
1060.520(b)(5)(ii)(B), you must separately measure permeation emissions 
from a fuel cap. You may show that your fuel tank and fuel cap meet 
emission standards by certifying them separately or by combining the 
separate measurements into a single emission rate based on the relative 
surface areas of the fuel tank and fuel cap. However, you may not 
combine these emission measurements if you test the fuel cap at a 
nominal temperature of 28  deg.C and you test the fuel tank at 40 
deg.C. Measure the fuel cap's permeation emissions as follows:
    (a) Select a fuel cap expected to have permeation emissions at least 
as high as the highest-emitting fuel cap that you expect to be used with 
fuel tanks from the emission family. Include a gasket that represents 
production models. If the fuel cap includes vent paths, seal these vents 
as follows:
    (1) If the vent path is through grooves in the gasket, you may use 
another gasket with no vent grooves if it is otherwise the same as a 
production gasket.
    (2) If the vent path is through the cap, seal any vents for testing.
    (b) Attach the fuel cap to a fuel tank with a capacity of at least 
one liter made of metal or some other impermeable material.
    (c) Use the procedures specified in Sec. 1060.520 to measure 
permeation emissions. Calculate emission rates using the smallest inside 
cross sectional area of the opening on which the cap is mounted as the 
fuel cap's surface area.



Sec. 1060.525  How do I test fuel systems for diurnal emissions?

    Use the procedures of this section to determine whether your fuel 
tanks meet diurnal emission standards as specified in Sec. 1060.105.
    (a) Use the following procedure to measure diurnal emissions:
    (1) Diurnal measurements are based on representative temperature 
cycles, as follows:
    (i) Diurnal fuel temperatures for marine fuel tanks that will be 
installed in nontrailerable boats must undergo repeat temperature swings 
of 2.6  deg.C between nominal values of 27.6 and 30.2  deg.C.
    (ii) Diurnal fuel temperatures for other installed marine fuel tanks 
must undergo repeat temperature swings of 6.6  deg.C between nominal 
values of 25.6 and 32.2  deg.C.
    (iii) For fuel tanks installed in equipment other than marine 
vessels, the following table specifies a profile of ambient 
temperatures:

 Table 1 to Sec. 1060.525--Diurnal Temperature Profiles for Nonmarine
                               Fuel Tanks
------------------------------------------------------------------------
                                                              Ambient
                                                            temperature
                      Time (hours)                         profile ( C)
 
------------------------------------------------------------------------
0.......................................................            22.2
1.......................................................            22.5
2.......................................................            24.2
3.......................................................            26.8
4.......................................................            29.6
5.......................................................            31.9
6.......................................................            33.9
7.......................................................            35.1
8.......................................................            35.4
9.......................................................            35.6
10......................................................            35.3
11......................................................            34.5
12......................................................            33.2
13......................................................            31.4
14......................................................            29.7
15......................................................            28.2
16......................................................            27.2
17......................................................            26.1
18......................................................            25.1
19......................................................            24.3
20......................................................            23.7
21......................................................            23.3
22......................................................            22.9
23......................................................            22.6
24......................................................            22.2
------------------------------------------------------------------------

    (2) Fill the fuel tank to 40 percent of nominal capacity with the 
gasoline specified in 40 CFR 1065.710 for general testing.
    (3) Install a vapor line from any vent ports that would not be 
sealed in the final in-use configuration. Use a length of vapor line 
representing the largest inside diameter and shortest length that would 
be expected with the range of in-use installations for the emission 
family.
    (4) If the fuel tank is equipped with a carbon canister, load the 
canister with

[[Page 33]]

butane or gasoline vapors to its canister working capacity as specified 
in Sec. 1060.240(e)(2)(i) and attach it to the fuel tank in a way that 
represents a typical in-use configuration. Purge the canister as follows 
to prepare for emission measurement:
    (i) For marine fuel tanks, perform a single heating and cooling 
cycle as specified in paragraph (a)(7) of this section without measuring 
emissions.
    (ii) For nonmarine fuel tanks, establish a characteristic purge 
volume by running an engine with the fuel tank installed to represent an 
in-use configuration. Measure the volume of air flowing through the 
canister while the engine operates for 30 minutes over repeat cycles of 
the appropriate duty cycle used for certifying the engine for exhaust 
emissions. Set up the loaded canister for testing by purging it with the 
characteristic purge volume from the engine simulation run.
    (5) Stabilize the fuel tank to be within 2.0  deg.C of the nominal 
starting temperature specified in paragraph (a)(1) of this section. In 
the case of marine fuel tanks, install a thermocouple meeting the 
requirements of 40 CFR 86.107-96(e) in the approximate mid-volume of 
fuel and record the temperature at the end of the stabilization period 
to the nearest 0.1  deg.C. For sealed fuel systems, replace the fuel cap 
once the fuel reaches equilibrium at the appropriate starting 
temperature.
    (6) Prepare the tank for mass measurement using one of the following 
procedures:
    (i) Place the stabilized fuel tank in a SHED meeting the 
specifications of 40 CFR 86.107-96(a)(1) that is equipped with a FID 
analyzer meeting the specifications of 40 CFR 1065.260. Take the 
following steps in sequence:
    (A) Purge the SHED.
    (B) Close and seal the SHED.
    (C) Zero and span the FID analyzer.
    (D) Within ten minutes of sealing the SHED, measure the initial 
hydrocarbon concentration. This is the start of the sampling period.
    (ii) If your testing configuration involves mass emissions at the 
standard of 2.0 grams or more, you may alternatively place the 
stabilized fuel tank in any temperature-controlled environment and 
establish mass emissions as a weight loss relative to a reference fuel 
tank using the procedure specified in Sec. 1060.520(d) instead of 
calculating it from changing hydrocarbon concentrations in the SHED.
    (7) Control temperatures as follows:
    (i) For marine fuel tanks, supply heat to the fuel tank for 
continuously increasing temperatures such that the fuel reaches the 
maximum temperature in 8 hours. Set the target temperature by adding the 
temperature swing specified in paragraph (a)(1) of this section to the 
recorded starting temperature. Hold the tank for approximately 60 
minutes at a temperature no less than 0.1  deg.C below the target 
temperature. For example, if the recorded starting fuel temperature for 
a fuel tank that will be installed in a nontrailerable vessel is 27.1 
deg.C, the target temperature is 29.7  deg.C and the fuel must be 
stabilized for 60 minutes with fuel temperatures not falling below 29.6 
deg.C. For EPA testing, fuel temperatures may not go 1.0  deg.C above 
the target temperature at any point during the heating or stabilization 
sequence. Measure the hydrocarbon concentration in the SHED at the end 
of the high-temperature stabilization period. Calculate the diurnal 
emissions for this heating period based on the change in hydrocarbon 
concentration over this sampling period. Allow the fuel temperature to 
cool sufficiently to stabilize again at the starting temperature without 
emission sampling. Repeat the heating and measurement sequence for three 
consecutive days, starting each heating cycle no more than 26 hours 
after the previous start.
    (ii) For nonmarine fuel tanks, follow the air temperature trace from 
paragraph (a)(1)(iii) of this section for three consecutive 24-hour 
periods. Measured temperatures must follow the profile with a maximum 
deviation of 1.7  deg.C for any hourly measurement and an average 
temperature deviation not to exceed 1.0  deg.C, where the average 
deviation is calculated using the absolute value of each measured 
deviation. Start measuring emissions when you start the temperature 
profile. The end of the first, second, and third emission sampling 
periods must occur 1440[6, 2880[6, and 4320[6 minutes, respectively, 
after starting the measurement procedure.

[[Page 34]]

    (8) Use the highest of the three emission levels to determine 
whether your fuel tank meets the diurnal emission standard.
    (9) For emission control technologies that rely on a sealed fuel 
system, you may omit the preconditioning steps in paragraph (a)(4) of 
this section and the last two 24-hour periods of emission measurements 
in paragraph (a)(7) of this section. For purposes of this paragraph (a), 
sealed fuel systems include those that rely on pressure-relief valves, 
limiting flow orifices, bladder fuel tanks, and volume-compensating air 
bags.
    (b) You may subtract your fuel tank's permeation emissions from the 
measured diurnal emissions if the fuel tank is preconditioned with 
diurnal test fuel as described in Sec. 1060.520(b) or if you use good 
engineering judgment to otherwise establish that the fuel tank has 
stabilized permeation emissions. Measure permeation emissions for 
subtraction as specified in Sec. 1060.520(c) and (d) before measuring 
diurnal emissions, except that the permeation measurement must be done 
with diurnal test fuel at 28[2  deg.C. Use appropriate units and 
corrections to subtract the permeation emissions from the fuel tank 
during the diurnal emission test. You may not subtract a greater mass of 
emissions under this paragraph (b) than the fuel tank would emit based 
on meeting the applicable emission standard for permeation.

[80 FR 9117, Feb. 19, 2015]



                 Subpart G_Special Compliance Provisions



Sec. 1060.601  How do the prohibitions of 40 CFR 1068.101 apply with
respect to the requirements of this part?

    (a) As described in Sec. 1060.1, fuel tanks and fuel lines that are 
used with or intended to be used with new nonroad engines or equipment 
are subject to evaporative emission standards under this part 1060. This 
includes portable marine fuel tanks and fuel lines and other fuel-system 
components associated with portable marine fuel tanks. Note that Sec. 
1060.1 specifies an implementation schedule based on the date of 
manufacture of nonroad equipment, so new fuel tanks and fuel lines are 
not subject to standards under this part 1060 if they will be installed 
for use in equipment built before the specified dates for implementing 
the appropriate standards, subject to the limitations in paragraph (b) 
of this section. Except as specified in paragraph (f) of this section, 
fuel-system components that are subject to permeation or diurnal 
emission standards under this part 1060 must be covered by a valid 
certificate of conformity before being introduced into U.S. commerce to 
avoid violating the prohibition of 40 CFR 1068.101(a). To the extent we 
allow it under the exhaust standard-setting part, fuel-system components 
may be certified with a family emission limit higher than the specified 
emission standard. The provisions of this paragraph (a) do not apply to 
fuel caps.
    (b) New replacement fuel tanks and fuel lines must meet the 
requirements of this part 1060 if they are intended to be used with 
nonroad engines or equipment regulated under this part 1060, as follows:
    (1) Applicability of standards between January 1, 2012 and December 
31, 2019. Manufacturers, distributors, retailers, and importers must 
clearly state on the packaging for all replacement components that could 
reasonably be used with nonroad engines how such components may be used 
consistent with the prohibition in paragraph (a) of this section. It is 
presumed that such components are intended for use with nonroad engines 
regulated under this part 1060 unless the components, or the packaging 
for such components, clearly identify appropriate restrictions. This 
requirement does not apply for components that are clearly not intended 
for use with fuels.
    (2) Applicability of standards after January 1, 2020. Starting 
January 1, 2020 it is presumed that replacement components will be used 
with nonroad engines regulated under this part 1060 if they can 
reasonably be used with such engines. Manufacturers, distributors, 
retailers, and importers are therefore obligated to take reasonable 
steps to ensure that any uncertified components are not used to replace 
certified

[[Page 35]]

components. This would require labeling the components and may also 
require restricting the sales and requiring the ultimate purchaser to 
agree to not use the components inappropriately. This requirement does 
not apply for components that are clearly not intended for use with 
fuels.
    (3) Applicability of the tampering prohibition. If a fuel tank or 
fuel line needing replacement was certified to meet the emission 
standards in this part with a family emission limit below the otherwise 
applicable standard, the new replacement fuel tank or fuel line must be 
certified to current emission standards, but need not be certified with 
the same or lower family emission limit to avoid violating the tampering 
prohibition in 40 CFR 1068.101(b)(1).
    (c) [Reserved]
    (d) Manufacturers that generate or use evaporative emission credits 
related to Marine SI engines in 40 CFR part 1045 or Small SI engines in 
40 CFR part 1054 are subject to the emission standards for which they 
are generating or using evaporative emission credits. These engines or 
equipment must therefore be covered by a valid certificate of conformity 
showing compliance with emission-credit provisions before being 
introduced into U.S. commerce to avoid violating the prohibition of 40 
CFR 1068.101(a).
    (e) If there is no valid certificate of conformity for any given 
evaporative emission standard for new equipment, the manufacturers of 
the engine, equipment and fuel-system components are each liable for 
violations of the prohibited acts with respect to the fuel systems and 
fuel-system components they have introduced into U.S. commerce, 
including fuel systems and fuel-system components installed in engines 
or equipment at the time the engines or equipment are introduced into 
U.S. commerce.
    (f) If you manufacture fuel lines or fuel tanks that are subject to 
the requirements of this part as described in paragraph (a) of this 
section, 40 CFR 1068.101(a) does not prohibit you from shipping your 
products directly to an equipment manufacturer or another manufacturer 
from which you have received a written commitment to be responsible for 
certifying the components as required under this part 1060. This 
includes SHED-based certification of Small SI equipment as described in 
Sec. 1060.105. If you ship fuel lines or fuel tanks under this 
paragraph (f), you must include documentation that accompanies the 
shipped products identifying the name and address of the company 
receiving shipment and stating that the fuel lines or fuel tanks are 
exempt under the provisions of 40 CFR 1060.601(f).
    (g) If new evaporative emission standards apply in a given model 
year, your equipment in that model year must have fuel-system components 
that are certified to the new standards, except that you may continue to 
use up your normal inventory of earlier fuel-system components that were 
built before the date of the new or changed standards. For example, if 
your normal inventory practice is to keep on hand a one-month supply of 
fuel tanks based on your upcoming production schedules, and a new tier 
of standards starts to apply for the 2012 model year, you may order fuel 
tanks based on your normal inventory requirements late in the fuel tank 
manufacturer's 2011 model year and install those fuel tanks in your 
equipment, regardless of the date of installation. Also, if your model 
year starts before the end of the calendar year preceding new standards, 
you may use fuel-system components from the previous model year (or 
uncertified components if no standards were in place) for those units 
you produce before January 1 of the year that new standards apply. If 
emission standards do not change in a given model year, you may continue 
to install fuel-system components from the previous model year without 
restriction. You may not circumvent the provisions of 40 CFR 
1068.101(a)(1) by stockpiling fuel-system components that were built 
before new or changed standards take effect.
    (h) If equipment manufacturers hold certificates of conformity for 
their equipment but they use only fuel-system components that have been 
certified by other companies, they may satisfy their defect-reporting 
obligations by tracking the information described in 40 CFR 
1068.501(b)(1) related

[[Page 36]]

to possible defects, reporting this information to the appropriate 
component manufacturers, and keeping these records for eight years. Such 
equipment manufacturers will not be considered in violation of 40 CFR 
1068.101(b)(6) for failing to perform investigations, make calculations, 
or submit reports to EPA as specified in 40 CFR 1068.501. See Sec. 
1060.5(a).

[73 FR 59298, Oct. 8, 2008, as amended at 75 FR 23027, Apr. 30, 2010]



Sec. 1060.605  Exemptions from evaporative emission standards.

    (a) Except as specified in the exhaust standard-setting part and 
paragraph (b) of this section, equipment using an engine that is exempt 
from exhaust emission standards under the provisions in 40 CFR part 
1068, subpart C or D, is also exempt from the requirements of this part 
1060. For example, engines or equipment exempted from exhaust emission 
standards for purposes of national security do not need to meet 
evaporative emission standards. Also, any engine that is exempt from 
emission standards because it will be used solely for competition does 
not need to meet evaporative emission standards. Equipment that is 
exempt from all exhaust emission standards under the standard-setting 
part are also exempt from the requirements of this part 1060; however, 
this does not apply for engines that must meet a less stringent exhaust 
emission standard as a condition of the exemption.
    (b) Engines produced under the replacement-engine exemption in 40 
CFR 1068.240 must use fuel-system components that meet the evaporative 
emission standards based on the model year of the engine being replaced 
subject to the provisions of 40 CFR 1068.265. If no evaporative emission 
standards applied at that time, no requirements related to evaporative 
emissions apply to the new engine. Installing a replacement engine does 
not change the applicability of requirements for the equipment into 
which the replacement engine is installed.
    (c) Engines or equipment that are temporarily exempt from EPA 
exhaust emission standards are also exempt from the requirements of this 
part 1060 for the same period as the exhaust exemption.
    (d) For equipment powered by more than one engine, all the engines 
installed in the equipment must be exempt from all applicable EPA 
exhaust emission standards for the equipment to also be exempt under 
paragraph (a) or (b) of this section.
    (e) In unusual circumstances, we may exempt components or equipment 
from the requirements of this part 1060 even if the equipment is powered 
by one or more engines that are subject to EPA exhaust emission 
standards. See 40 CFR part 1068. Such exemptions will be limited to:
    (1) Testing. See 40 CFR 1068.210.
    (2) National security. See 40 CFR 1068.225.
    (3) Economic hardship. See 40 CFR 1068.245 and 1068.250.
    (f) Evaporative emission standards generally apply based on the 
model year of the equipment, which is determined by the equipment's date 
of final assembly. However, in the first year of new emission standards, 
equipment manufacturers may apply evaporative emission standards based 
on the model year of the engine as shown on the engine's emission 
control information label. For example, for fuel tank permeation 
standards starting in 2012, equipment manufacturers may order a batch of 
2011 model year engines for installation in 2012 model year equipment, 
subject to the anti-stockpiling provisions of 40 CFR 1068.105(a). The 
equipment with the 2011 model year engines would not need to meet fuel 
tank permeation standards as long as the equipment is fully assembled by 
December 31, 2012.



Sec. 1060.640  What special provisions apply to branded equipment?

    The following provisions apply if you identify the name and 
trademark of another company instead of your own on your emission 
control information label for equipment, as provided by Sec. Sec. 
1060.135 and 1060.137:
    (a) You must have a contractual agreement with the other company 
that obligates that company to take the following steps:
    (1) Meet the emission warranty requirements that apply under Sec. 
1060.120.

[[Page 37]]

This may involve a separate agreement involving reimbursement of 
warranty-related expenses.
    (2) Report all warranty-related information to the certificate 
holder.
    (b) In your application for certification, identify the company 
whose trademark you will use and describe the arrangements you have made 
to meet your requirements under this section.
    (c) You remain responsible for meeting all the requirements of this 
chapter, including warranty and defect-reporting provisions.



          Subpart H_Averaging, Banking, and Trading Provisions



Sec. 1060.701  Applicability.

    (a) You are allowed to comply with the emission standards in this 
part with evaporative emission credits only if the exhaust standard-
setting part explicitly allows it for evaporative emissions.
    (b) The following exhaust standard-setting parts allow some use of 
evaporative emission credits:
    (1) 40 CFR part 1045 for marine vessels.
    (2) 40 CFR part 1051 for recreational vehicles.
    (3) 40 CFR part 1054 for Small SI equipment.
    (c) As specified in 40 CFR part 1048, there is no allowance to 
generate or use emission credits with Large SI equipment.



Sec. 1060.705  How do I certify components to an emission level other
than the standard under this part or use such components in my 
equipment?

    As specified in this section, a fuel-system component may be 
certified to a family emission limit (FEL) instead of the otherwise 
applicable emission standard. Note that the exhaust standard-setting 
part may apply maximum values for an FEL (i.e., FEL caps).
    (a) Requirements for certifying component manufacturers. See subpart 
C of this part for instructions regarding the general requirements for 
certifying components.
    (1) When you submit your application for certification, indicate the 
FEL to which your components will be certified. This FEL will serve as 
the applicable standard for your component, and the equipment that uses 
the component. For example, when the regulations of this part use the 
phrase ``demonstrate compliance with the applicable emission standard'' 
it will mean ``demonstrate compliance with the FEL'' for your component.
    (2) You may not change the FEL for an emission family. To specify a 
different FEL for your components, you must send a new application for 
certification for a new emission family.
    (3) Unless your FEL is below all emission standards that could 
potentially apply, you must ensure that all equipment manufacturers that 
will use your component are aware of the limitations regarding the 
conditions under which they may use your component.
    (4) It is your responsibility to read the instructions relative to 
emission-credit provisions in the standard-setting parts identified in 
Sec. 1060.1.
    (b) Requirements for equipment manufacturers. See subpart C of this 
part for instructions regarding your ability to rely on the component 
manufacturer's certificate.
    (1) The FEL of the component will serve as the applicable standard 
for your equipment.
    (2) You may not specify more than one FEL for an emission family at 
one time; however, you may change the FEL during the model year as 
described in Sec. 1060.225(f).
    (3) If the FEL is above the emission standard you must ensure that 
the exhaust standard-setting part allows you to use evaporative emission 
credits to comply with emission standards and that you will have an 
adequate source of evaporative emission credits. You must certify your 
equipment as specified in Sec. 1060.201 and the rest of subpart C of 
this part.



          Subpart I_Definitions and Other Reference Information



Sec. 1060.801  What definitions apply to this part?

    The following definitions apply to this part. The definitions apply 
to all subparts unless we note otherwise. All undefined terms have the 
meaning the

[[Page 38]]

Clean Air Act gives to them. The definitions follow:
    Accuracy and precision means the sum of accuracy and repeatability, 
as defined in 40 CFR 1065.1001. For example, if a measurement device is 
determined to have an accuracy of [1% and a repeatability of [2%, then 
its accuracy and precision would be [3%.
    Adjustable parameter means any device, system, or element of design 
that someone can adjust and that, if adjusted, may affect emissions. You 
may ask us to exclude a parameter if you show us that it will not be 
adjusted in use in a way that affects emissions.
    Applicable emission standard or applicable standard means an 
emission standard to which a fuel-system component is subject. 
Additionally, if a fuel-system component has been or is being certified 
to another standard or FEL, applicable emission standard means the FEL 
or other standard to which the fuel-system component has been or is 
being certified. This definition does not apply to subpart H of this 
part.
    Canister working capacity means the measured amount of hydrocarbon 
vapor that can be stored in a canister as specified in Sec. 
1060.240(e)(2)(i).
    Carbon working capacity means the measured amount of hydrocarbon 
vapor that can be stored in a given volume of carbon when tested 
according to ASTM D5228 (incorporated by reference in Sec. 1060.810). 
See Sec. 1060.240(e)(2)(ii).
    Certification means relating to the process of obtaining a 
certificate of conformity for an emission family that complies with the 
emission standards and requirements in this part.
    Certified emission level means the highest official emission result 
in an emission family.
    Clean Air Act means the Clean Air Act, as amended, 42 U.S.C. 7401-
7671q.
    Cold-weather equipment is limited to the following types of handheld 
equipment: Chainsaws, cut-off saws, clearing saws, brush cutters with 
engines at or above 40cc, commercial earth and wood drills, and ice 
augers. This includes earth augers if they are also marketed as ice 
augers.
    Configuration means a unique combination of hardware (material, 
geometry, and size) and calibration within an emission family. Units 
within a single configuration differ only with respect to normal 
production variability.
    Date of manufacture, means one of the following with respect to 
equipment:
    (1) For outboard engines with under-cowl fuel tanks and for vessels 
equipped with outboard engines and installed fuel tanks, date of 
manufacture means the date on which the fuel tank is installed.
    (2) For all other equipment, date of manufacture has the meaning 
given in 40 CFR 1068.30.
    Days means calendar days unless otherwise specified. For example, 
when we specify working days we mean calendar days, excluding weekends 
and U.S. national holidays.
    Designated Compliance Officer means the Manager, Heavy-Duty and 
Nonroad Engine Group (6405-J), U.S. Environmental Protection Agency, 
1200 Pennsylvania Ave., NW., Washington, DC 20460.
    Detachable fuel line means a fuel line or fuel line assembly 
intended to be used with a portable nonroad fuel tank and which is 
connected by special fittings to the fuel tank and/or engine for easy 
disassembly. Fuel lines that require a wrench or other tools to 
disconnect are not considered detachable fuel lines. Fuel lines that are 
labeled or marketed as USCG Type B1 fuel line as specified in 33 CFR 
183.540 are not considered detachable fuel lines if they are sold to the 
ultimate purchaser without quick-connect fittings or similar hardware.
    Diurnal emissions means evaporative emissions that occur as a result 
of venting fuel tank vapors during daily temperature changes while the 
engine is not operating.
    Effective length-to-diameter ratio means the mean vapor path length 
of a carbon canister divided by the effective diameter of that vapor 
path. The effective diameter is the diameter of a circle with the same 
cross-sectional area as the average cross-sectional area of the carbon 
canister's vapor path.
    Emission control system means any device, system, or element of 
design that controls or reduces the regulated evaporative emissions from 
a piece of nonroad equipment.

[[Page 39]]

    Emission-data unit means a fuel line, fuel tank, fuel system, or 
fuel-system component that is tested for certification. This includes 
components tested by EPA.
    Emission family has the meaning given in Sec. 1060.230.
    Emission-related maintenance means maintenance that substantially 
affects emissions or is likely to substantially affect emission 
deterioration.
    Equipment means vehicles, marine vessels, and other types of nonroad 
equipment that are subject to this part's requirements.
    Evaporative means relating to fuel emissions that result from 
permeation of fuel through the fuel-system materials or from ventilation 
of the fuel system.
    Exhaust standard-setting part means the part in the Code of Federal 
Regulations that contains exhaust emission standards for a particular 
piece of equipment (or the engine in that piece of equipment). For 
example, the exhaust standard-setting part for off-highway motorcycles 
is 40 CFR part 1051. Exhaust standard-setting parts may include 
evaporative emission requirements or describe how the requirements of 
this part 1060 apply.
    Exposed gasket surface area means the surface area of the gasket 
inside the fuel tank that is exposed to fuel or fuel vapor. For the 
purposes of calculating exposed surface area of a gasket, the thickness 
of the gasket and the outside dimension of the opening being sealed are 
used. Gasket overhang into the fuel tank should be ignored for the 
purpose of this calculation.
    Family emission limit (FEL) means an emission level declared by the 
manufacturer to serve in place of an otherwise applicable emission 
standard under an ABT program specified by the exhaust standard-setting 
part. The family emission limit must be expressed to the same number of 
decimal places as the emission standard it replaces. The family emission 
limit serves as the emission standard for the emission family with 
respect to all required testing.
    Fuel CE10 has the meaning given in Sec. 1060.515(a).
    Fuel line means hoses or tubing designed to contain liquid fuel. The 
exhaust standard-setting part may further specify which types of hoses 
and tubing are subject to the standards of this part.
    Fuel system means all components involved in transporting, metering, 
and mixing the fuel from the fuel tank to the combustion chamber(s), 
including the fuel tank, fuel tank cap, fuel pump, fuel filters, fuel 
lines, carburetor or fuel-injection components, and all fuel-system 
vents. In the case where the fuel tank cap or other components 
(excluding fuel lines) are directly mounted on the fuel tank, they are 
considered to be a part of the fuel tank.
    Fuel type means a general category of fuels such as gasoline or 
natural gas. There can be multiple grades within a single fuel type, 
such as premium gasoline, regular gasoline, or gasoline with 10 percent 
ethanol.
    Gasoline means one of the following:
    (1) For in-use fuels, gasoline means fuel that is commonly and 
commercially know as gasoline, including ethanol blends.
    (2) For testing, gasoline has the meaning given in subpart F of this 
part.
    Good engineering judgment means judgments made consistent with 
generally accepted scientific and engineering principles and all 
available relevant information. See 40 CFR 1068.5 for the administrative 
process we use to evaluate good engineering judgment.
    High-permeability material means any nonmetal material that does not 
qualify as low-permeability material.
    Installed marine fuel line means a fuel line designed for delivering 
fuel to a Marine SI engine that does not meet the definition of portable 
marine fuel line.
    Installed marine fuel tank means a fuel tank designed for delivering 
fuel to a Marine SI engine that does not meet the definition of portable 
marine fuel tanks.
    Large SI means relating to engines that are subject to evaporative 
emission standards in 40 CFR part 1048.
    Low-permeability material means, for gaskets, a material with 
permeation emission rates at or below 10 (g-mm)/m\2\/day when measured 
according to SAE J2659 (incorporated by reference

[[Page 40]]

in Sec. 1060.810), where the test temperature is 23  deg.C, the test 
fuel is Fuel CE10, and testing immediately follows a four-week 
preconditioning soak with the test fuel.
    Manufacture means the physical and engineering process of designing, 
constructing, and assembling an engine, piece of nonroad equipment, or 
fuel-system components subject to the requirements of this part.
    Manufacturer has the meaning given in section 216(1) of the Clean 
Air Act (42 U.S.C. 7550(1)). In general, this term includes:
    (1) Any person who manufactures an engine or piece of nonroad 
equipment for sale in the United States or otherwise introduces a new 
nonroad engine or a piece of new nonroad equipment into U.S. commerce.
    (2) Any person who manufactures a fuel-system component for an 
engine subject to the requirements of this part as described in Sec. 
1060.1(a).
    (3) Importers who import such products into the United States.
    Marine SI means relating to vessels powered by engines that are 
subject to exhaust emission standards in 40 CFR part 1045.
    Marine vessel has the meaning given in 40 CFR Sec. 1045.801, which 
generally includes all nonroad equipment used as a means of 
transportation on water.
    Model year means one of the following things:
    (1) For equipment defined as ``new nonroad equipment'' under 
paragraph (1) of the definition of ``new nonroad engine,'' model year 
means one of the following:
    (i) Calendar year.
    (ii) Your annual new model production period if it is different than 
the calendar year. This must include January 1 of the calendar year for 
which the model year is named. It may not begin before January 2 of the 
previous calendar year and it must end by December 31 of the named 
calendar year.
    (2) For other equipment defined as ``new nonroad equipment'' under 
paragraph (2) of the definition of ``new nonroad engine,'' model year 
has the meaning given in the exhaust standard-setting part.
    (3) For other equipment defined as ``new nonroad equipment'' under 
paragraph (3) or paragraph (4) of the definition of ``new nonroad 
engine,'' model year means the model year of the engine as defined in 
the exhaust standard-setting part.
    New nonroad equipment means equipment meeting one or more of the 
following criteria:
    (1) Nonroad equipment for which the ultimate purchaser has never 
received the equitable or legal title. The equipment is no longer new 
when the ultimate purchaser receives this title or the product is placed 
into service, whichever comes first.
    (2) Nonroad equipment that is defined as new under the exhaust 
standard-setting part. (Note: equipment that is not defined as new under 
the exhaust standard-setting part may be defined as new under this 
definition of ``new nonroad equipment.'')
    (3) Nonroad equipment with an engine that becomes new (as defined in 
the exhaust standard-setting part) while installed in the equipment. The 
equipment is no longer new when it is subsequently placed into service. 
This paragraph (3) does not apply if the engine becomes new before being 
installed in the equipment.
    (4) Nonroad equipment not covered by a certificate of conformity 
issued under this part at the time of importation and manufactured after 
the requirements of this part start to apply (see Sec. 1060.1). The 
equipment is no longer new when it is subsequently placed into service. 
Importation of this kind of new nonroad equipment is generally 
prohibited by 40 CFR part 1068.
    Nominal capacity means a fuel tank's volume as specified by the fuel 
tank manufacturer, using at least two significant figures, based on the 
maximum volume of fuel the tank can hold with standard refueling 
techniques.
    Nonroad engine has the meaning we give in 40 CFR 1068.30. In general 
this means all internal-combustion engines except motor vehicle engines, 
stationary engines, engines used solely for competition, or engines used 
in aircraft. This part does not apply to all nonroad engines (see Sec. 
1060.1).
    Nonroad equipment means a piece of equipment that is powered by or 
intended to be powered by one or more nonroad engines. Note that 
Sec. Sec. 1060.5 and

[[Page 41]]

1060.601 describes how we treat outboard engines, portable marine fuel 
tanks, and associated fuel-system components as nonroad equipment under 
this part 1060.
    Nontrailerable boat means a vessel whose length is 26.0 feet or 
more, or whose width is more than 8.5 feet.
    Official emission result means the measured emission rate for an 
emission-data unit.
    Placed into service means put into initial use for its intended 
purpose.
    Portable marine fuel line means a detachable fuel line that is used 
or intended to be used to supply fuel to a marine engine during 
operation. This also includes any fuel line labeled or marketed at USCG 
Type B1 fuel line as specified in 33 CFR 183.540, whether or not it 
includes detachable connecting hardware; this is often called universal 
fuel line.
    Portable marine fuel tank means a portable fuel tank that is used or 
intended to be used to supply fuel to a marine engine during operation.
    Portable nonroad fuel tank means a fuel tank that meets each of the 
following criteria:
    (1) It has design features indicative of use in portable 
applications, such as a carrying handle and fuel line fitting that can 
be readily attached to and detached from a nonroad engine.
    (2) It has a nominal fuel capacity of 12 gallons or less.
    (3) It is designed to supply fuel to an engine while the engine is 
operating.
    (4) It is not used or intended to be used to supply fuel to a marine 
engine.
    Production period means the period in which a component or piece of 
equipment will be produced under a certificate of conformity. A given 
production period for an emission family may not include components 
certified using different test data. A production period may not exceed 
five years for certified components. Note that the definition of model 
year includes specifications related to production periods for which a 
certificate is valid for equipment.
    Recreational vehicle means vehicles that are subject to evaporative 
emission standards in 40 CFR part 1051. This generally includes engines 
that will be installed in recreational vehicles if the engines are 
certified separately under 40 CFR 1051.20.
    Relating to as used in this section means relating to something in a 
specific, direct manner. This expression is used in this section only to 
define terms as adjectives and not to broaden the meaning of the terms.
    Revoke has the meaning given in 40 CFR 1068.30. If we revoke a 
certificate or an exemption, you must apply for a new certificate or 
exemption before continuing to introduce the affected equipment into 
U.S. commerce.
    Round means to round numbers according to standard procedures as 
specified in 40 CFR 1065.1001.
    Running loss emissions means unburned fuel vapor that escapes from 
the fuel system to the ambient atmosphere while the engine is operating, 
excluding permeation emissions and diurnal emissions. Running loss 
emissions generally result from fuel-temperature increases caused by 
heat released from in-tank fuel pumps, fuel recirculation, or proximity 
to heat sources such as the engine or exhaust components.
    Sealed means lacking openings to the atmosphere that would allow a 
measurable amount of liquid or vapor to leak out under normal operating 
pressures or other pressures specified in this part. For example, you 
may generally establish a maximum value for operating pressures based on 
the highest pressure you would observe from an installed fuel tank 
during continuous equipment operation on a sunny day with ambient 
temperatures of 35  deg.C. A fuel system may be considered to have no 
measurable leak if it does not release bubbles when held underwater at 
the identified tank pressure for 60 seconds. This determination presumes 
the use of good engineering judgment; for example, it would not be 
appropriate to test the fuel tank such that small leaks would avoid 
detection by collecting in a cavity created by holding the tank with a 
certain orientation. Sealed fuel systems may have openings for emission 
controls or for fuel lines needed to route fuel to the engine.
    Small SI means relating to engines that are subject to emission 
standards in 40 CFR part 90 or 1054.

[[Page 42]]

    Structurally integrated nylon fuel tank means a fuel tank having all 
the following characteristics:
    (1) The fuel tank is made of a polyamide material that does not 
contain more than 50 percent by weight of a reinforcing glass fiber or 
mineral filler and does not contain more than 10 percent by weight of 
impact modified polyamides that use rubberized agents such as EPDM 
rubber.
    (2) The fuel tank must be used in a cut-off saw or chainsaw or be 
integrated into a major structural member where, as a single component, 
the fuel tank material is a primary structural/stress member for other 
major components such as the engine, transmission, or cutting 
attachment.
    Subchapter U means 40 CFR parts 1000 through 1299.
    Suspend has the meaning given in 40 CFR 1068.30. If we suspend a 
certificate, you may not introduce into U.S. commerce equipment from 
that emission family unless we reinstate the certificate or approve a 
new one. If we suspend an exemption, you may not introduce into U.S. 
commerce equipment that was previously covered by the exemption unless 
we reinstate the exemption.
    Tare means to use a container or other reference mass to zero a 
balance before weighing a sample. Generally, this means placing the 
container or reference mass on the balance, allowing it to stabilize, 
then zeroing the balance without removing the container or reference 
mass. This allows you to use the balance to determine the difference in 
mass between the sample and the container or reference mass.
    Test sample means the collection of fuel lines, fuel tanks, or fuel 
systems selected from the population of an emission family for emission 
testing. This may include certification testing or any kind of 
confirmatory testing.
    Test unit means a piece of fuel line, a fuel tank, or a fuel system 
in a test sample.
    Ultimate purchaser means, with respect to any new nonroad equipment, 
the first person who in good faith purchases such new nonroad equipment 
for purposes other than resale.
    Ultraviolet light means electromagnetic radiation with a wavelength 
between 300 and 400 nanometers.
    United States has the meaning given in 40 CFR 1068.30.
    U.S.-directed production volume means the amount of equipment, 
subject to the requirements of this part, produced by a manufacturer for 
which the manufacturer has a reasonable assurance that sale was or will 
be made to ultimate purchasers in the United States.
    Useful life means the period during which new nonroad equipment is 
required to comply with all applicable emission standards. See Sec. 
1060.101.
    Void has the meaning given in 40 CFR 1068.30. In general this means 
to invalidate a certificate or an exemption both retroactively and 
prospectively.
    Volatile liquid fuel means any fuel other than diesel or biodiesel 
that is a liquid at atmospheric pressure and has a Reid Vapor Pressure 
higher than 2.0 pounds per square inch.
    We (us, our) means the Administrator of the Environmental Protection 
Agency and any authorized representatives.
    Wintertime equipment means equipment using a wintertime engine, as 
defined in 40 CFR 1054.801. Note this definition applies only for Small 
SI equipment.

[73 FR 59298, Oct. 8, 2008, as amended at 75 FR 23027, Apr. 30, 2010]



Sec. 1060.805  What symbols, acronyms, and abbreviations does this
part use?

    The following symbols, acronyms, and abbreviations apply to this 
part:

 deg. degree.
ASTM American Society for Testing and Materials.
C Celsius.
CFR Code of Federal Regulations.
EPA Environmental Protection Agency.
FEL family emission limit.
g gram.
gal gallon.
hr hour.
in inch.
kPa kilopascal.
kW kilowatt.
L liter.
m meter.
min minute.
mm millimeter.

[[Page 43]]

psig pounds per square inch of gauge pressure.
SAE Society of Automotive Engineers.
SHED Sealed Housing for Evaporative Determination.
U.S. United States.
U.S.C. United States Code.
W watt.



Sec. 1060.810  What materials does this part reference?

    (a) Materials incorporated by reference. Certain material is 
incorporated by reference into this part with the approval of the 
Director of the Federal Register under 5 U.S.C. 552(a) and 1 CFR part 
51. To enforce any edition other than that specified in this section, a 
document must be published in the Federal Register and the material must 
be available to the public. All approved material is available for 
inspection at U.S. EPA, Air and Radiation Docket and Information Center, 
1301 Constitution Ave. NW., Room B102, EPA West Building, Washington, DC 
20460, (202) 202-1744, and is available from the sources listed below. 
It is also available for inspection at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to http://www.archives.gov/
federal--register/code--of--federal--regulations/ibr--locations.html.
    (b) ASTM International material. The following standards are 
available from ASTM International, 100 Barr Harbor Drive, P.O. Box C700, 
West Conshohocken, PA, 19428-2959, (610) 832-9585, or http://
www.astm.org/:
    (1) ASTM D471-06, Standard Test Method for Rubber Property--Effect 
of Liquids, approved October 1, 2006 (``ASTM D471''), IBR approved for 
Sec. 1060.515(a).
    (2) ASTM D2862-97 (Reapproved 2004), Standard Test Method for 
Particle Size Distribution of Granular Activated Carbon, approved April 
1, 2004 (``ASTM D2862''), IBR approved for Sec. 1060.240(e).
    (3) ASTM D3802-79 (Reapproved 2005), Standard Test Method for Ball-
Pan Hardness of Activated Carbon, approved October 1, 2005 (``ASTM 
D3802''), IBR approved for Sec. 1060.240(e).
    (4) ASTM D4806-07, Standard Specification for Denatured Fuel Ethanol 
for Blending with Gasolines for Use as Automotive Spark-Ignition Engine 
Fuel, approved July 15, 2007 (``ASTM D4806''), IBR approved for Sec. 
1060.501(c).
    (5) ASTM D5228-92 (Reapproved 2005), Standard Test Method for 
Determination of Butane Working Capacity of Activated Carbon, approved 
October 1, 2005 (``ASTM D5228''), IBR approved for Sec. 1060.801.
    (c) SAE International material. The following standards are 
available from SAE International, 400 Commonwealth Dr., Warrendale, PA 
15096-0001, (877) 606-7323 (U.S. and Canada) or (724) 776-4970 (outside 
the U.S. and Canada), or http://www.sae.org:
    (1) SAE J30, Fuel and Oil Hoses, Revised June 1998, IBR approved for 
Sec. 1060.515(c).
    (2) SAE J1527, Marine Fuel Hoses, Revised February 1993, IBR 
approved for Sec. 1060.515(c).
    (3) SAE J2260, Nonmetallic Fuel System Tubing with One or More 
Layers, Revised November 2004, IBR approved for Sec. 1060.510.
    (4) SAE J2659, Test Method to Measure Fluid Permeation of Polymeric 
Materials by Speciation, Issued December 2003, IBR approved for Sec. 
1060.801.
    (5) SAE J2996, Surface Vehicle Recommended Practice, Small Diameter 
Fuel Line Permeation Test Procedure, Issued January 2013, IBR approved 
for Sec. 1060.515(d).
    (d) California Air Resources Board. The following documents are 
available from the California Air Resources Board, 1001 I Street, 
Sacramento, CA, 95812, (916) 322-2884, or http://www.arb.ca.gov:
    (1) Final Regulation Order, Article 1, Chapter 15, Division 3, Title 
13, California Code of Regulations, July 26, 2004, IBR approved for 
Sec. 1060.105(e), and 1060.240(e).
    (2) [Reserved]
    (e) American Boat and Yacht Council Material. The following 
documents are available from the American Boat and Yacht Council, 613 
Third Street, Suite 10, Annapolis, MD 21403 or (410) 990-4460 or http://
www.abycinc.org/:
    (1) ABYC H-25, Portable Marine Gasoline Fuel Systems, July 2010, IBR 
approved for Sec. 1060.105(f).

[[Page 44]]

    (2) [Reserved]

[80 FR 9117, Feb. 19, 2015]



Sec. 1060.815  What provisions apply to confidential information?

    (a) Clearly show what you consider confidential by marking, 
circling, bracketing, stamping, or some other method.
    (b) We will store your confidential information as described in 40 
CFR part 2. Also, we will disclose it only as specified in 40 CFR part 
2. This applies both to any information you send us and to any 
information we collect from inspections, audits, or other site visits.
    (c) If you send us a second copy without the confidential 
information, we will assume it contains nothing confidential whenever we 
need to release information from it.
    (d) If you send us information without claiming it is confidential, 
we may make it available to the public without further notice to you, as 
described in 40 CFR 2.204.



Sec. 1060.820  How do I request a hearing?

    (a) You may request a hearing under certain circumstances as 
described elsewhere in this part. To do this, you must file a written 
request, including a description of your objection and any supporting 
data, within 30 days after we make a decision.
    (b) For a hearing you request under the provisions of this part, we 
will approve your request if we find that your request raises a 
substantial factual issue.
    (c) If we agree to hold a hearing, we will use the procedures 
specified in 40 CFR part 1068, subpart G.



Sec. 1060.825  What reporting and recordkeeping requirements apply
under this part?

    Under the Paperwork Reduction Act (44 U.S.C. 3501 et seq), the 
Office of Management and Budget approves the reporting and recordkeeping 
specified in the applicable regulations. The following items illustrate 
the kind of reporting and recordkeeping we require for products 
regulated under this part:
    (a) We specify the following requirements related to equipment 
certification in this part 1060:
    (1) In 40 CFR 1060.20 we give an overview of principles for 
reporting information.
    (2) In 40 CFR part 1060, subpart C, we identify a wide range of 
information required to certify engines.
    (3) In 40 CFR 1060.301 we require manufacturers to make engines or 
equipment available for our testing if we make such a request.
    (4) In 40 CFR 1060.505 we specify information needs for establishing 
various changes to published test procedures.
    (b) We specify the following requirements related to the general 
compliance provisions in 40 CFR part 1068:
    (1) In 40 CFR 1068.5 we establish a process for evaluating good 
engineering judgment related to testing and certification.
    (2) In 40 CFR 1068.25 we describe general provisions related to 
sending and keeping information.
    (3) In 40 CFR 1068.27 we require manufacturers to make equipment 
available for our testing or inspection if we make such a request.
    (4) In 40 CFR 1068.105 we require equipment manufacturers to keep 
certain records related to duplicate labels from engine manufacturers.
    (5) [Reserved]
    (6) In 40 CFR part 1068, subpart C, we identify several reporting 
and recordkeeping items for making demonstrations and getting approval 
related to various exemptions.
    (7) In 40 CFR part 1068, subpart D, we identify several reporting 
and recordkeeping items for making demonstrations and getting approval 
related to importing equipment.
    (8) In 40 CFR 1068.450 and 1068.455 we specify certain records 
related to testing production-line products in a selective enforcement 
audit.
    (9) In 40 CFR 1068.501 we specify certain records related to 
investigating and reporting emission-related defects.
    (10) In 40 CFR 1068.525 and 1068.530 we specify certain records 
related to recalling nonconforming equipment.

[[Page 45]]



PART 1065_ENGINE-TESTING PROCEDURES--Table of Contents



             Subpart A_Applicability and General Provisions

Sec.
1065.1 Applicability.
1065.2 Submitting information to EPA under this part.
1065.5 Overview of this part 1065 and its relationship to the standard-
          setting part.
1065.10 Other procedures.
1065.12 Approval of alternate procedures.
1065.15 Overview of procedures for laboratory and field testing.
1065.20 Units of measure and overview of calculations.
1065.25 Recordkeeping.

                   Subpart B_Equipment Specifications

1065.101 Overview.
1065.110 Work inputs and outputs, accessory work, and operator demand.
1065.120 Fuel properties and fuel temperature and pressure.
1065.122 Engine cooling and lubrication.
1065.125 Engine intake air.
1065.127 Exhaust gas recirculation.
1065.130 Engine exhaust.
1065.140 Dilution for gaseous and PM constituents.
1065.145 Gaseous and PM probes, transfer lines, and sampling system 
          components.
1065.150 Continuous sampling.
1065.170 Batch sampling for gaseous and PM constituents.
1065.190 PM-stabilization and weighing environments for gravimetric 
          analysis.
1065.195 PM-stabilization environment for in-situ analyzers.

                    Subpart C_Measurement Instruments

1065.201 Overview and general provisions.
1065.202 Data updating, recording, and control.
1065.205 Performance specifications for measurement instruments.

         Measurement of Engine Parameters and Ambient Conditions

1065.210 Work input and output sensors.
1065.215 Pressure transducers, temperature sensors, and dewpoint 
          sensors.

                        Flow-Related Measurements

1065.220 Fuel flow meter.
1065.225 Intake-air flow meter.
1065.230 Raw exhaust flow meter.
1065.240 Dilution air and diluted exhaust flow meters.
1065.245 Sample flow meter for batch sampling.
1065.247 Diesel exhaust fluid flow rate.
1065.248 Gas divider.

                   CO and CO2 Measurements

1065.250 Nondispersive infrared analyzer.

                        Hydrocarbon Measurements

1065.260 Flame ionization detector.
1065.265 Nonmethane cutter.
1065.266 Fourier transform infrared analyzer.
1065.267 Gas chromatograph with a flame ionization detector.
1065.269 Photoacoustic analyzer for ethanol and methanol.

             NOX and N2O Measurements

1065.270 Chemiluminescent detector.
1065.272 Nondispersive ultraviolet analyzer.
1065.275 N2O measurement devices.

                       O2 Measurements

1065.280 Paramagnetic and magnetopneumatic O2 detection 
          analyzers.

                     Air-to-Fuel Ratio Measurements

1065.284 Zirconia (ZrO2) analyzer.

                             PM Measurements

1065.290 PM gravimetric balance.
1065.295 PM inertial balance for field-testing analysis.

                Subpart D_Calibrations and Verifications

1065.301 Overview and general provisions.
1065.303 Summary of required calibration and verifications.
1065.305 Verifications for accuracy, repeatability, and noise.
1065.307 Linearity verification.
1065.308 Continuous gas analyzer system-response and updating-recording 
          verification--for gas analyzers not continuously compensated 
          for other gas species.
1065.309 Continuous gas analyzer system-response and updating-recording 
          verification--for gas analyzers continuously compensated for 
          other gas species.

         Measurement of Engine Parameters and Ambient Conditions

1065.310 Torque calibration.
1065.315 Pressure, temperature, and dewpoint calibration.

                        Flow-Related Measurements

1065.320 Fuel-flow calibration.
1065.325 Intake-flow calibration.
1065.330 Exhaust-flow calibration.
1065.340 Diluted exhaust flow (CVS) calibration.
1065.341 CVS, PFD, and batch sampler verification (propane check).

[[Page 46]]

1065.342 Sample dryer verification.
1065.345 Vacuum-side leak verification.

                   CO and CO2 Measurements

1065.350 H2O interference verification for CO2 
          NDIR analyzers.
1065.355 H2O and CO2 interference verification for 
          CO NDIR analyzers.

                        Hydrocarbon Measurements

1065.360 FID optimization and verification.
1065.362 Non-stoichiometric raw exhaust FID O2 interference 
          verification.
1065.365 Nonmethane cutter penetration fractions.
1065.366 Interference verification for FTIR analyzers.
1065.369 H[bdi2] O, CO, and CO[bdi2] interference verification for 
          photoacoustic alcohol analyzers.

             NOX and N2O Measurements

1065.370 CLD CO2 and H2O quench verification.
1065.372 NDUV analyzer HC and H2O interference verification.
1065.375 Interference verification for N2O analyzers.
1065.376 Chiller NO2 penetration.
1065.378 NO2-to-NO converter conversion verification.

                             PM Measurements

1065.390 PM balance verifications and weighing process verification.
1065.395 Inertial PM balance verifications.

        Subpart E_Engine Selection, Preparation, and Maintenance

1065.401 Test engine selection.
1065.405 Test engine preparation and maintenance.
1065.410 Maintenance limits for stabilized test engines.
1065.415 Durability demonstration.

    Subpart F_Performing an Emission Test Over Specified Duty Cycles

1065.501 Overview.
1065.510 Engine mapping.
1065.512 Duty cycle generation.
1065.514 Cycle-validation criteria for operation over specified duty 
          cycles.
1065.516 Sample system decontamination and preconditioning.
1065.518 Engine preconditioning.
1065.520 Pre-test verification procedures and pre-test data collection.
1065.525 Engine starting, restarting, and shutdown.
1065.526 Repeating of void modes or test intervals.
1065.530 Emission test sequence.
1065.545 Verification of proportional flow control for batch sampling.
1065.546 Verification of minimum dilution ratio for PM batch sampling.
1065.550 Gas analyzer range verification and drift verification.
1065.590 PM sampling media (e.g., filters) preconditioning and tare 
          weighing.
1065.595 PM sample post-conditioning and total weighing.

              Subpart G_Calculations and Data Requirements

1065.601 Overview.
1065.602 Statistics.
1065.610 Duty cycle generation.
1065.630 Local acceleration of gravity.
1065.640 Flow meter calibration calculations.
1065.642 PDP, SSV, and CFV molar flow rate calculations.
1065.644 Vacuum-decay leak rate.
1065.645 Amount of water in an ideal gas.
1065.650 Emission calculations.
1065.655 Chemical balances of fuel, intake air, and exhaust.
1065.659 Removed water correction.
1065.660 THC, NMHC, NMNEHC, CH4, and 
          C2H6 determination.
1065.665 THCE and NMHCE determination.
1065.667 Dilution air background emission correction.
1065.670 NOX intake-air humidity and temperature corrections.
1065.672 Drift correction.
1065.675 CLD quench verification calculations.
1065.680 Adjusting emission levels to account for infrequently 
          regenerating aftertreatment devices.
1065.690 Buoyancy correction for PM sample media.
1065.695 Data requirements.

    Subpart H_Engine Fluids, Test Fuels, Analytical Gases and Other 
                          Calibration Standards

1065.701 General requirements for test fuels.
1065.703 Distillate diesel fuel.
1065.705 Residual and intermediate residual fuel.
1065.710 Gasoline.
1065.715 Natural gas.
1065.720 Liquefied petroleum gas.
1065.725 High-level ethanol-gasoline blends.
1065.735 Diesel exhaust fluid.
1065.740 Lubricants.
1065.745 Coolants.
1065.750 Analytical gases.
1065.790 Mass standards.

                 Subpart I_Testing with Oxygenated Fuels

1065.801 Applicability.
1065.805 Sampling system.

[[Page 47]]

1065.845 Response factor determination.
1065.850 Calculations.

    Subpart J_Field Testing and Portable Emission Measurement Systems

1065.901 Applicability.
1065.905 General provisions.
1065.910 PEMS auxiliary equipment for field testing.
1065.915 PEMS instruments.
1065.920 PEMS calibrations and verifications.
1065.925 PEMS preparation for field testing.
1065.930 Engine starting, restarting, and shutdown.
1065.935 Emission test sequence for field testing.
1065.940 Emission calculations.

          Subpart K_Definitions and Other Reference Information

1065.1001 Definitions.
1065.1005 Symbols, abbreviations, acronyms, and units of measure.
1065.1010 Incorporation by reference.

        Subpart L_Methods for Unregulated and Special Pollutants

1065.1101 Applicability.
1065.1102 Semi-Volatile Organic Compounds
1065.1103 General provisions for SVOC measurement.
1065.1105 Sampling system design.
1065.1107 Sample media and sample system preparation; sampler assembly.
1065.1109 Post-test sampler disassembly and sample extraction.
1065.1111 Sample analysis.

    Authority: 42 U.S.C. 7401-7671q.

    Source: 70 FR 40516, July 13, 2005, unless otherwise noted.



             Subpart A_Applicability and General Provisions



Sec. 1065.1  Applicability.

    (a) This part describes the procedures that apply to testing we 
require for the following engines or for vehicles using the following 
engines:
    (1) Locomotives we regulate under 40 CFR part 1033. For earlier 
model years, manufacturers may use the test procedures in this part or 
those specified in 40 CFR part 92 according to Sec. 1065.10.
    (2) Model year 2010 and later heavy-duty highway engines we regulate 
under 40 CFR part 86. For earlier model years, manufacturers may use the 
test procedures in this part or those specified in 40 CFR part 86, 
subpart N, according to Sec. 1065.10.
    (3) Nonroad diesel engines we regulate under 40 CFR part 1039 and 
stationary compression-ignition engines that are certified to the 
standards in 40 CFR part 1039, as specified in 40 CFR part 60, subpart 
IIII. For earlier model years, manufacturers may use the test procedures 
in this part or those specified in 40 CFR part 89 according to Sec. 
1065.10.
    (4) Marine diesel engines we regulate under 40 CFR part 1042 and 
stationary compression-ignition engines that are certified to the 
standards in 40 CFR part 1042, as specified in 40 CFR part 60, subpart 
IIII. For earlier model years, manufacturers may use the test procedures 
in this part or those specified in 40 CFR part 94 according to Sec. 
1065.10.
    (5) Marine spark-ignition engines we regulate under 40 CFR part 
1045. For earlier model years, manufacturers may use the test procedures 
in this part or those specified in 40 CFR part 91 according to Sec. 
1065.10.
    (6) Large nonroad spark-ignition engines we regulate under 40 CFR 
part 1048, and stationary engines that are certified to the standards in 
40 CFR part 1048 or as otherwise specified in 40 CFR part 60, subpart 
JJJJ.
    (7) Vehicles we regulate under 40 CFR part 1051 (such as snowmobiles 
and off-highway motorcycles) based on engine testing. See 40 CFR part 
1051, subpart F, for standards and procedures that are based on vehicle 
testing.
    (8) Small nonroad spark-ignition engines we regulate under 40 CFR 
part 1054 and stationary engines that are certified to the standards in 
40 CFR part 1054 as specified in 40 CFR part 60, subpart JJJJ. For 
earlier model years, manufacturers may use the test procedures in this 
part or those specified in 40 CFR part 90 according to Sec. 1065.10.
    (b) The procedures of this part may apply to other types of engines, 
as described in this part and in the standard-setting part.
    (c) The term ``you'' means anyone performing testing under this part 
other than EPA.
    (1) This part is addressed primarily to manufacturers of engines, 
vehicles, equipment, and vessels, but it applies

[[Page 48]]

equally to anyone who does testing under this part for such 
manufacturers.
    (2) This part applies to any manufacturer or supplier of test 
equipment, instruments, supplies, or any other goods or services related 
to the procedures, requirements, recommendations, or options in this 
part.
    (d) Paragraph (a) of this section identifies the parts of the CFR 
that define emission standards and other requirements for particular 
types of engines. In this part, we refer to each of these other parts 
generically as the ''standard-setting part.'' For example, 40 CFR part 
1051 is always the standard-setting part for snowmobiles. Note that 
while 40 CFR part 86 is the standard-setting part for heavy-duty highway 
engines, this refers specifically to 40 CFR part 86, subpart A, and to 
certain portions of 40 CFR part 86, subpart N, as described in 40 CFR 
86.1301.
    (e) Unless we specify otherwise, the terms ``procedures'' and ``test 
procedures'' in this part include all aspects of engine testing, 
including the equipment specifications, calibrations, calculations, and 
other protocols and procedural specifications needed to measure 
emissions.
    (f) For vehicles, equipment, or vessels subject to this part and 
regulated under vehicle-based, equipment-based, or vessel-based 
standards, use good engineering judgment to interpret the term 
``engine'' in this part to include vehicles, equipment, or vessels, 
where appropriate.
    (g) For additional information regarding these test procedures, 
visit our Web site at http://www.epa.gov, and in particular http://
www.epa.gov/nvfel/testing/regulations.htm.
    (h) This part describes procedures and specifications for measuring 
an engine's exhaust emissions. While the measurements are geared toward 
engine-based measurements (in units of g/kW [middot] hr), many of these 
provisions apply equally to vehicle-based measurements (in units of g/
mile or g/kilometer). 40 CFR part 1066 describes the analogous 
procedures for vehicle-based emission measurements, and in many cases 
states that specific provisions of this part 1065 also apply for those 
vehicle-based measurements. Where material from this part 1065 applies 
for vehicle-based measurements under 40 CFR part 1066, it is sometimes 
necessary to include parenthetical statements in this part 1065 to 
properly cite secondary references that are different for vehicle-based 
testing. See 40 CFR part 1066 and the standard-setting part for 
additional information.

[73 FR 37288, June 30, 2008, as amended at 73 FR 59321, Oct. 8, 2008; 75 
FR 23028, Apr. 30, 2010; 76 FR 37977, June 28, 2011; 76 FR 57437, Sept. 
15, 2011; 79 FR 23752, Apr. 28, 2014]



Sec. 1065.2  Submitting information to EPA under this part.

    (a) You are responsible for statements and information in your 
applications for certification, requests for approved procedures, 
selective enforcement audits, laboratory audits, production-line test 
reports, field test reports, or any other statements you make to us 
related to this part 1065. If you provide statements or information to 
someone for submission to EPA, you are responsible for these statements 
and information as if you had submitted them to EPA yourself.
    (b) In the standard-setting part and in 40 CFR 1068.101, we describe 
your obligation to report truthful and complete information and the 
consequences of failing to meet this obligation. See also 18 U.S.C. 1001 
and 42 U.S.C. 7413(c)(2). This obligation applies whether you submit 
this information directly to EPA or through someone else.
    (c) We may void any certificates or approvals associated with a 
submission of information if we find that you intentionally submitted 
false, incomplete, or misleading information. For example, if we find 
that you intentionally submitted incomplete information to mislead EPA 
when requesting approval to use alternate test procedures, we may void 
the certificates for all engines families certified based on emission 
data collected using the alternate procedures. This would also apply if 
you ignore data from incomplete tests or from repeat tests with higher 
emission results.
    (d) We may require an authorized representative of your company to 
approve and sign the submission, and to certify that all the information 
submitted is accurate and complete. This

[[Page 49]]

includes everyone who submits information, including manufacturers and 
others.
    (e) See 40 CFR 1068.10 for provisions related to confidential 
information. Note however that under 40 CFR 2.301, emission data are 
generally not eligible for confidential treatment.
    (f) Nothing in this part should be interpreted to limit our ability 
under Clean Air Act section 208 (42 U.S.C. 7542) to verify that engines 
conform to the regulations.

[73 FR 37289, June 30, 2008, as amended at 75 FR 23028, Apr. 30, 2010; 
79 FR 23752, Apr. 28, 2014]



Sec. 1065.5  Overview of this part 1065 and its relationship to the 
standard-setting part.

    (a) This part specifies procedures that apply generally to testing 
various categories of engines. See the standard-setting part for 
directions in applying specific provisions in this part for a particular 
type of engine. Before using this part's procedures, read the standard-
setting part to answer at least the following questions:
    (1) What duty cycles must I use for laboratory testing?
    (2) Should I warm up the test engine before measuring emissions, or 
do I need to measure cold-start emissions during a warm-up segment of 
the duty cycle?
    (3) Which exhaust constituents do I need to measure? Measure all 
exhaust constituents that are subject to emission standards, any other 
exhaust constituents needed for calculating emission rates, and any 
additional exhaust constituents as specified in the standard-setting 
part. Alternatively, you may omit the measurement of N2O and 
CH4 for an engine, provided it is not subject to an 
N2O or CH4 emission standard. If you omit the 
measurement of N2O and CH4, you must provide other 
information and/or data that will give us a reasonable basis for 
estimating the engine's emission rates.
    (4) Do any unique specifications apply for test fuels?
    (5) What maintenance steps may I take before or between tests on an 
emission-data engine?
    (6) Do any unique requirements apply to stabilizing emission levels 
on a new engine?
    (7) Do any unique requirements apply to test limits, such as ambient 
temperatures or pressures?
    (8) Is field testing required or allowed, and are there different 
emission standards or procedures that apply to field testing?
    (9) Are there any emission standards specified at particular engine-
operating conditions or ambient conditions?
    (10) Do any unique requirements apply for durability testing?
    (b) The testing specifications in the standard-setting part may 
differ from the specifications in this part. In cases where it is not 
possible to comply with both the standard-setting part and this part, 
you must comply with the specifications in the standard-setting part. 
The standard-setting part may also allow you to deviate from the 
procedures of this part for other reasons.
    (c) The following table shows how this part divides testing 
specifications into subparts:

       Table 1 of Sec. 1065.5--Description of Part 1065 Subparts
------------------------------------------------------------------------
                                   Describes these specifications or
         This subpart                          procedures
------------------------------------------------------------------------
Subpart A....................  Applicability and general provisions.
Subpart B....................  Equipment for testing.
Subpart C....................  Measurement instruments for testing.
Subpart D....................  Calibration and performance verifications
                                for measurement systems.
Subpart E....................  How to prepare engines for testing,
                                including service accumulation.
Subpart F....................  How to run an emission test over a
                                predetermined duty cycle.
Subpart G....................  Test procedure calculations.
Subpart H....................  Fuels, engine fluids, analytical gases,
                                and other calibration standards.
Subpart I....................  Special procedures related to oxygenated
                                fuels.
Subpart J....................  How to test with portable emission
                                measurement systems (PEMS).
------------------------------------------------------------------------


[[Page 50]]


[73 FR 37289, June 30, 2008, as amended at 74 FR 56511, Oct. 30, 2009]



Sec. 1065.10  Other procedures.

    (a) Your testing. The procedures in this part apply for all testing 
you do to show compliance with emission standards, with certain 
exceptions noted in this section. In some other sections in this part, 
we allow you to use other procedures (such as less precise or less 
accurate procedures) if they do not affect your ability to show that 
your engines comply with the applicable emission standards. This 
generally requires emission levels to be far enough below the applicable 
emission standards so that any errors caused by greater imprecision or 
inaccuracy do not affect your ability to state unconditionally that the 
engines meet all applicable emission standards.
    (b) Our testing. These procedures generally apply for testing that 
we do to determine if your engines comply with applicable emission 
standards. We may perform other testing as allowed by the Act.
    (c) Exceptions. We may allow or require you to use procedures other 
than those specified in this part in the following cases, which may 
apply to laboratory testing, field testing, or both. We intend to 
publicly announce when we allow or require such exceptions. All of the 
test procedures noted here as exceptions to the specified procedures are 
considered generically as ``other procedures.'' Note that the terms 
``special procedures'' and ``alternate procedures'' have specific 
meanings; ``special procedures'' are those allowed by Sec. 
1065.10(c)(2) and ``alternate procedures'' are those allowed by Sec. 
1065.10(c)(7).
    (1) The objective of the procedures in this part is to produce 
emission measurements equivalent to those that would result from 
measuring emissions during in-use operation using the same engine 
configuration as installed in a vehicle, equipment, or vessel. However, 
in unusual circumstances where these procedures may result in 
measurements that do not represent in-use operation, you must notify us 
if good engineering judgment indicates that the specified procedures 
cause unrepresentative emission measurements for your engines. Note that 
you need not notify us of unrepresentative aspects of the test procedure 
if measured emissions are equivalent to in-use emissions. This provision 
does not obligate you to pursue new information regarding the different 
ways your engine might operate in use, nor does it obligate you to 
collect any other in-use information to verify whether or not these test 
procedures are representative of your engine's in-use operation. If you 
notify us of unrepresentative procedures under this paragraph (c)(1), we 
will cooperate with you to establish whether and how the procedures 
should be appropriately changed to result in more representative 
measurements. While the provisions of this paragraph (c)(1) allow us to 
be responsive to issues as they arise, we would generally work toward 
making these testing changes generally applicable through rulemaking. We 
will allow reasonable lead time for compliance with any resulting change 
in procedures. We will consider the following factors in determining the 
importance of pursuing changes to the procedures:
    (i) Whether supplemental emission standards or other requirements in 
the standard-setting part address the type of operation of concern or 
otherwise prevent inappropriate design strategies.
    (ii) Whether the unrepresentative aspect of the procedures affects 
your ability to show compliance with the applicable emission standards.
    (iii) The extent to which the established procedures require the use 
of emission-control technologies or strategies that are expected to 
ensure a comparable degree of emission control under the in-use 
operation that differs from the specified procedures.
    (2) You may request to use special procedures if your engine cannot 
be tested using the specified procedures. For example, this may apply if 
your engine cannot operate on the specified duty cycle. In this case, 
tell us in writing why you cannot satisfactorily test your engine using 
this part's procedures and ask to use a different approach. We will 
approve your request if we determine that it would produce emission 
measurements that represent in-use operation and we determine that

[[Page 51]]

it can be used to show compliance with the requirements of the standard-
setting part. Where we approve special procedures that differ 
substantially from the specified procedures, we may preclude you from 
participating in averaging, banking, and trading with the affected 
engine families.
    (3) In a given model year, you may use procedures required for later 
model year engines without request. If you upgrade your testing facility 
in stages, you may rely on a combination of procedures for current and 
later model year engines as long as you can ensure, using good 
engineering judgment, that the combination you use for testing does not 
affect your ability to show compliance with the applicable emission 
standards.
    (4) In a given model year, you may ask to use procedures allowed for 
earlier model year engines. We will approve this only if you show us 
that using the procedures allowed for earlier model years does not 
affect your ability to show compliance with the applicable emission 
standards.
    (5) You may ask to use emission data collected using other 
procedures, such as those of the California Air Resources Board or the 
International Organization for Standardization. We will approve this 
only if you show us that using these other procedures does not affect 
your ability to show compliance with the applicable emission standards.
    (6) During the 12 months following the effective date of any change 
in the provisions of this part 1065 (and 40 CFR part 1066 for vehicle 
testing), you may use data collected using procedures specified in the 
previously applicable version of this part 1065 (and 40 CFR part 1066 
for vehicle testing). This also applies for changes to test procedures 
specified in the standard-setting part to the extent that these changes 
do not correspond to new emission standards. This paragraph (c)(6) does 
not restrict the use of carryover certification data otherwise allowed 
by the standard-setting part.
    (7) You may request to use alternate procedures that are equivalent 
to the specified procedures, or procedures that are more accurate or 
more precise than the specified procedures. We may perform tests with 
your engines using either the approved alternate procedures or the 
specified procedures. The following provisions apply to requests for 
alternate procedures:
    (i) Applications. Follow the instructions in Sec. 1065.12.
    (ii) Submission. Submit requests in writing to the Designated 
Compliance Officer.
    (iii) Notification. We may approve your request by telling you 
directly, or we may issue guidance announcing our approval of a specific 
alternate procedure, which would make additional requests for approval 
unnecessary.
    (d) Advance approval. If we require you to request approval to use 
other procedures under paragraph (c) of this section, you may not use 
them until we approve your request.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37290, June 30, 2008; 
75 FR 23028, Apr. 30, 2010; 79 FR 23752, Apr. 28, 2014; 80 FR 9118, Feb. 
19, 2015; 81 FR 74162, Oct. 25, 2016]



Sec. 1065.12  Approval of alternate procedures.

    (a) To get approval for an alternate procedure under Sec. 
1065.10(c), send the Designated Compliance Officer an initial written 
request describing the alternate procedure and why you believe it is 
equivalent to the specified procedure. Anyone may request alternate 
procedure approval. This means that an individual engine manufacturer 
may request to use an alternate procedure. This also means that an 
instrument manufacturer may request to have an instrument, equipment, or 
procedure approved as an alternate procedure to those specified in this 
part. We may approve your request based on this information alone, 
whether or not it includes all the information specified in this 
section. Where we determine that your original submission does not 
include enough information for us to determine that the alternate 
procedure is equivalent to the specified procedure, we may ask you to 
submit supplemental information showing that your alternate procedure is 
consistently and reliably at least as accurate and repeatable as the 
specified procedure.
    (b) We may make our approval under this section conditional upon 
meeting other requirements or specifications.

[[Page 52]]

We may limit our approval, for example, to certain time frames, specific 
duty cycles, or specific emission standards. Based upon any supplemental 
information we receive after our initial approval, we may amend a 
previously approved alternate procedure to extend, limit, or discontinue 
its use. We intend to publicly announce alternate procedures that we 
approve.
    (c) Although we will make every effort to approve only alternate 
procedures that completely meet our requirements, we may revoke our 
approval of an alternate procedure if new information shows that it is 
significantly not equivalent to the specified procedure.
    If we do this, we will grant time to switch to testing using an 
allowed procedure, considering the following factors:
    (1) The cost, difficulty, and availability to switch to a procedure 
that we allow.
    (2) The degree to which the alternate procedure affects your ability 
to show that your engines comply with all applicable emission standards.
    (3) Any relevant factors considered in our initial approval.
    (d) If we do not approve your proposed alternate procedure based on 
the information in your initial request, we may ask you to send 
additional information to fully evaluate your request. While we consider 
the information specified in this paragraph (d) and the statistical 
criteria of paragraph (e) of this section to be sufficient to 
demonstrate equivalence, it may not be necessary to include all the 
information or meet the specified statistical criteria. For example, 
systems that do not meet the statistical criteria in paragraph (e) of 
this section because they have a small bias toward high emission results 
could be approved since they would not adversely affect your ability to 
demonstrate compliance with applicable standards.
    (1) Theoretical basis. Give a brief technical description explaining 
why you believe the proposed alternate procedure should result in 
emission measurements equivalent to those using the specified procedure. 
You may include equations, figures, and references. You should consider 
the full range of parameters that may affect equivalence. For example, 
for a request to use a different NOX measurement procedure, 
you should theoretically relate the alternate detection principle to the 
specified detection principle over the expected concentration ranges for 
NO, NO2, and interference gases. For a request to use a 
different PM measurement procedure, you should explain the principles by 
which the alternate procedure quantifies particulate mass similarly to 
the specified procedures.
    (2) Technical description. Describe briefly any hardware or software 
needed to perform the alternate procedure. You may include dimensioned 
drawings, flowcharts, schematics, and component specifications. Explain 
any necessary calculations or other data manipulation.
    (3) Procedure execution. Describe briefly how to perform the 
alternate procedure and recommend a level of training an operator should 
have to achieve acceptable results.
    Summarize the installation, calibration, operation, and maintenance 
procedures in a step-by-step format. Describe how any calibration is 
performed using NIST-traceable standards or other similar standards we 
approve. Calibration must be specified by using known quantities and 
must not be specified as a comparison with other allowed procedures.
    (4) Data-collection techniques. Compare measured emission results 
using the proposed alternate procedure and the specified procedure, as 
follows:
    (i) Both procedures must be calibrated independently to NIST-
traceable standards or to other similar standards we approve.
    (ii) Include measured emission results from all applicable duty 
cycles. Measured emission results should show that the test engine meets 
all applicable emission standards according to specified procedures.
    (iii) Use statistical methods to evaluate the emission measurements, 
such as those described in paragraph (e) of this section.
    (e) Absent any other directions from us, use a t-test and an F-test 
calculated according to Sec. 1065.602 to evaluate

[[Page 53]]

whether your proposed alternate procedure is equivalent to the specified 
procedure. We may give you specific directions regarding methods for 
statistical analysis, or we may approve other methods that you propose. 
Such alternate methods may be more or less stringent than those 
specified in this paragraph (e). In determining the appropriate 
statistical criteria, we will consider the repeatability of measurements 
made with the reference procedure. For example, less stringent 
statistical criteria may be appropriate for measuring emission levels 
being so low that they adversely affect the repeatability of reference 
measurements. We recommend that you consult a statistician if you are 
unfamiliar with these statistical tests. Perform the tests as follows:
    (1) Repeat measurements for all applicable duty cycles at least 
seven times for each procedure. You may use laboratory duty cycles to 
evaluate field-testing procedures.
    Be sure to include all available results to evaluate the precision 
and accuracy of the proposed alternate procedure, as described in Sec. 
1065.2.
    (2) Demonstrate the accuracy of the proposed alternate procedure by 
showing that it passes a two-sided t-test. Use an unpaired t-test, 
unless you show that a paired t-test is appropriate under both of the 
following provisions:
    (i) For paired data, the population of the paired differences from 
which you sampled paired differences must be independent. That is, the 
probability of any given value of one paired difference is unchanged by 
knowledge of the value of another paired difference. For example, your 
paired data would violate this requirement if your series of paired 
differences showed a distinct increase or decrease that was dependent on 
the time at which they were sampled.
    (ii) For paired data, the population of paired differences from 
which you sampled the paired differences must have a normal (i.e., 
Gaussian) distribution. If the population of paired difference is not 
normally distributed, consult a statistician for a more appropriate 
statistical test, which may include transforming the data with a 
mathematical function or using some kind of non-parametric test.
    (3) Show that t is less than the critical t value, tcrit, tabulated 
in Sec. 1065.602, for the following confidence intervals:
    (i) 90% for a proposed alternate procedure for laboratory testing.
    (ii) 95% for a proposed alternate procedure for field testing.
    (4) Demonstrate the precision of the proposed alternate procedure by 
showing that it passes an F-test. Use a set of at least seven samples 
from the reference procedure and a set of at least seven samples from 
the alternate procedure to perform an F-test. The sets must meet the 
following requirements:
    (i) Within each set, the values must be independent. That is, the 
probability of any given value in a set must be unchanged by knowledge 
of another value in that set. For example, your data would violate this 
requirement if a set showed a distinct increase or decrease that was 
dependent upon the time at which they were sampled.
    (ii) For each set, the population of values from which you sampled 
must have a normal (i.e., Gaussian) distribution. If the population of 
values is not normally distributed, consult a statistician for a more 
appropriate statistical test, which may include transforming the data 
with a mathematical function or using some kind of non-parametric test.
    (iii) The two sets must be independent of each other. That is, the 
probability of any given value in one set must be unchanged by knowledge 
of another value in the other set. For example, your data would violate 
this requirement if one value in a set showed a distinct increase or 
decrease that was dependent upon a value in the other set. Note that a 
trend of emission changes from an engine would not violate this 
requirement.
    (iv) If you collect paired data for the paired t-test in paragraph 
(e)(2) in this section, use caution when selecting sets from paired data 
for the F-test. If you do this, select sets that do not mask the 
precision of the measurement procedure. We recommend selecting such sets 
only from data collected using the same engine, measurement instruments, 
and test cycle.

[[Page 54]]

    (5) Show that F is less than the critical F value, Fcrit, tabulated 
in Sec. 1065.602. If you have several F-test results from several sets 
of data, show that the mean F-test value is less than the mean critical 
F value for all the sets. Evaluate Fcrit, based on the following 
confidence intervals:
    (i) 90% for a proposed alternate procedure for laboratory testing.
    (ii) 95% for a proposed alternate procedure for field testing.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37290, June 30, 2008; 
79 FR 23752, Apr. 28, 2014]



Sec. 1065.15  Overview of procedures for laboratory and field testing.

    This section outlines the procedures to test engines that are 
subject to emission standards.
    (a) In the standard-setting part, we set brake-specific emission 
standards in g/(kW [middot] hr) (or g/(hp [middot] hr)), for the 
following constituents:
    (1) Total oxides of nitrogen, NOX.
    (2) Hydrocarbon, HC, which may be expressed in the following ways:
    (i) Total hydrocarbon, THC.
    (ii) Nonmethane hydrocarbon, NMHC, which results from subtracting 
methane, CH4, from THC.
    (iii) Nonmethane-nonethane hydrocarbon, NMNEHC, which results from 
subtracting methane, CH4, and ethane, 
C2H6, from THC.
    (iv) Total hydrocarbon-equivalent, THCE, which results from 
adjusting THC mathematically to be equivalent on a carbon-mass basis.
    (v) Nonmethane hydrocarbon-equivalent, NMHCE, which results from 
adjusting NMHC mathematically to be equivalent on a carbon-mass basis.
    (3) Particulate matter, PM.
    (4) Carbon monoxide, CO.
    (5) Carbon dioxide, CO2.
    (6) Methane, CH4.
    (7) Nitrous oxide, N2O.
    (b) Note that some engines are not subject to standards for all the 
emission constituents identified in paragraph (a) of this section. Note 
also that the standard-setting part may include standards for pollutants 
not listed in paragraph (a) of this section.
    (c) We generally set brake-specific emission standards over test 
intervals and/or duty cycles, as follows:
    (1) Engine operation. Testing may involve measuring emissions and 
work in a laboratory-type environment or in the field, as described in 
paragraph (f) of this section. For most laboratory testing, the engine 
is operated over one or more duty cycles specified in the standard-
setting part. However, laboratory testing may also include non-duty 
cycle testing (such as simulation of field testing in a laboratory). For 
field testing, the engine is operated under normal in-use operation. The 
standard-setting part specifies how test intervals are defined for field 
testing. Refer to the definitions of ``duty cycle'' and ``test 
interval'' in Sec. 1065.1001. Note that a single duty cycle may have 
multiple test intervals and require weighting of results from multiple 
test intervals to calculate a composite brake-specific emissions value 
to compare to the standard.
    (2) Constituent determination. Determine the total mass of each 
constituent over a test interval by selecting from the following 
methods:
    (i) Continuous sampling. In continuous sampling, measure the 
constituent's concentration continuously from raw or dilute exhaust. 
Multiply this concentration by the continuous (raw or dilute) flow rate 
at the emission sampling location to determine the constituent's flow 
rate. Sum the constituent's flow rate continuously over the test 
interval. This sum is the total mass of the emitted constituent.
    (ii) Batch sampling. In batch sampling, continuously extract and 
store a sample of raw or dilute exhaust for later measurement. Extract a 
sample proportional to the raw or dilute exhaust flow rate. You may 
extract and store a proportional sample of exhaust in an appropriate 
container, such as a bag, and then measure NOX, HC, CO, 
CO2, CH4, N2O, and CH2O 
concentrations in the container after the test interval. You may deposit 
PM from proportionally extracted exhaust onto an appropriate substrate, 
such as a filter. In this case, divide the PM by the amount of filtered 
exhaust to calculate the PM concentration. Multiply batch sampled 
concentrations by the total (raw or dilute) flow from which it was 
extracted during the test interval. This

[[Page 55]]

product is the total mass of the emitted constituent.
    (iii) Combined sampling. You may use continuous and batch sampling 
simultaneously during a test interval, as follows:
    (A) You may use continuous sampling for some constituents and batch 
sampling for others.
    (B) You may use continuous and batch sampling for a single 
constituent, with one being a redundant measurement. See Sec. 1065.201 
for more information on redundant measurements.
    (3) Work determination. Determine work over a test interval by one 
of the following methods:
    (i) Speed and torque. Synchronously multiply speed and brake torque 
to calculate instantaneous values for engine brake power. Sum engine 
brake power over a test interval to determine total work.
    (ii) Fuel consumed and brake-specific fuel consumption. Directly 
measure fuel consumed or calculate it with chemical balances of the 
fuel, intake air, and exhaust. To calculate fuel consumed by a chemical 
balance, you must also measure either intake-air flow rate or exhaust 
flow rate. Divide the fuel consumed during a test interval by the brake-
specific fuel consumption to determine work over the test interval. For 
laboratory testing, calculate the brake-specific fuel consumption using 
fuel consumed and speed and torque over a test interval. For field 
testing, refer to the standard-setting part and Sec. 1065.915 for 
selecting an appropriate value for brake-specific fuel consumption.
    (d) Refer to Sec. 1065.650 for calculations to determine brake-
specific emissions.
    (e) The following figure illustrates the allowed measurement 
configurations described in this part 1065:

[[Page 56]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.019

    (f) This part 1065 describes how to test engines in a laboratory-
type environment or in the field.
    (1) This affects test intervals and duty cycles as follows:

[[Page 57]]

    (i) For laboratory testing, you generally determine brake-specific 
emissions for duty-cycle testing by using an engine dynamometer in a 
laboratory or other environment. This typically consists of one or more 
test intervals, each defined by a duty cycle, which is a sequence of 
modes, speeds, and/or torques (or powers) that an engine must follow. If 
the standard-setting part allows it, you may also simulate field testing 
with an engine dynamometer in a laboratory or other environment.
    (ii) Field testing consists of normal in-use engine operation while 
an engine is installed in a vehicle, equipment, or vessel rather than 
following a specific engine duty cycle. The standard-setting part 
specifies how test intervals are defined for field testing.
    (2) The type of testing may also affect what test equipment may be 
used. You may use ``lab-grade'' test equipment for any testing. The term 
``lab-grade'' refers to equipment that fully conforms to the applicable 
specifications of this part. For some testing you may alternatively use 
``field-grade'' equipment. The term ``field-grade'' refers to equipment 
that fully conforms to the applicable specifications of subpart J of 
this part, but does not fully conform to other specifications of this 
part. You may use ``field-grade'' equipment for field testing. We also 
specify in this part and in the standard-setting parts certain cases in 
which you may use ``field-grade'' equipment for testing in a laboratory-
type environment. (Note: Although ``field-grade'' equipment is generally 
more portable than ``lab-grade'' test equipment, portability is not 
relevant to whether equipment is considered to be ``field-grade'' or 
``lab-grade''.)

[70 FR 40516, July 13, 2005, as amended at 73 FR 37290, June 30, 2008; 
75 FR 23028, Apr. 30, 2010; 76 FR 57437, Sept. 15, 2011; 79 FR 23753, 
Apr. 28, 2014; 81 FR 74162, Oct. 25, 2016]



Sec. 1065.20  Units of measure and overview of calculations.

    (a) System of units. The procedures in this part generally follow 
the International System of Units (SI), as detailed in NIST Special 
Publication 811, which we incorporate by reference in Sec. 1065.1010. 
The following exceptions apply:
    (1) We designate angular speed, fn, of an engine's 
crankshaft in revolutions per minute (r/min), rather than the SI unit of 
radians per second (rad/s). This is based on the commonplace use of r/
min in many engine dynamometer laboratories.
    (2) We designate brake-specific emissions in grams per kilowatt-hour 
(g/(kW [middot] hr)), rather than the SI unit of grams per megajoule (g/
MJ). In addition, we use the symbol hr to identify hour, rather than the 
SI convention of using h. This is based on the fact that engines are 
generally subject to emission standards expressed in g/kW [middot] hr. 
If we specify engine standards in grams per horsepower [middot] hour (g/
(hp [middot] hr)) in the standard-setting part, convert units as 
specified in paragraph (d) of this section.
    (3) We generally designate temperatures in units of degrees Celsius 
(  deg.C) unless a calculation requires an absolute temperature. In that 
case, we designate temperatures in units of Kelvin (K). For conversion 
purposes throughout this part, 0  deg.C equals 273.15 K. Unless 
specified otherwise, always use absolute temperature values for 
multiplying or dividing by temperature.
    (b) Concentrations. This part does not rely on amounts expressed in 
parts per million. Rather, we express such amounts in the following SI 
units:
    (1) For ideal gases, [micro] mol/mol, formerly ppm (volume).
    (2) For all substances, cm\3\/m\3\, formerly ppm (volume).
    (3) For all substances, mg/kg, formerly ppm (mass).
    (c) Absolute pressure. Measure absolute pressure directly or 
calculate it as the sum of atmospheric pressure plus a differential 
pressure that is referenced to atmospheric pressure. Always use absolute 
pressure values for multiplying or dividing by pressure.
    (d) Units conversion. Use the following conventions to convert 
units:
    (1) Testing. You may record values and perform calculations with 
other units. For testing with equipment that involves other units, use 
the conversion factors from NIST Special Publication 811, as described 
in paragraph (a) of this section.

[[Page 58]]

    (2) Humidity. In this part, we identify humidity levels by 
specifying dewpoint, which is the temperature at which pure water begins 
to condense out of air. Use humidity conversions as described in Sec. 
1065.645.
    (3) Emission standards. If your standard is in g/(hp [middot] hr) 
units, convert kW to hp before any rounding by using the conversion 
factor of 1 hp (550 ft [middot] lbf/s) = 0.7456999 kW. Round the final 
value for comparison to the applicable standard.
    (e) Rounding. You are required to round certain final values, such 
as final emission values. You may round intermediate values when 
transferring data as long as you maintain at least six significant 
digits (which requires more than six decimal places for values less than 
0.1), or all significant digits if fewer than six digits are available. 
Unless the standard-setting part specifies otherwise, do not round other 
intermediate values. Round values to the number of significant digits 
necessary to match the number of decimal places of the applicable 
standard or specification as described in this paragraph (e). Note that 
specifications expressed as percentages have infinite precision (as 
described in paragraph (e)(7) of this section). Use the following 
rounding convention, which is consistent with ASTM E29 and NIST SP 811:
    (1) If the first (left-most) digit to be removed is less than five, 
remove all the appropriate digits without changing the digits that 
remain. For example, 3.141593 rounded to the second decimal place is 
3.14.
    (2) If the first digit to be removed is greater than five, remove 
all the appropriate digits and increase the lowest-value remaining digit 
by one. For example, 3.141593 rounded to the fourth decimal place is 
3.1416.
    (3) If the first digit to be removed is five with at least one 
additional non-zero digit following the five, remove all the appropriate 
digits and increase the lowest-value remaining digit by one. For 
example, 3.141593 rounded to the third decimal place is 3.142.
    (4) If the first digit to be removed is five with no additional non-
zero digits following the five, remove all the appropriate digits, 
increase the lowest-value remaining digit by one if it is odd and leave 
it unchanged if it is even. For example, 1.75 and 1.750 rounded to the 
first decimal place are 1.8; while 1.85 and 1.850 rounded to the first 
decimal place are also 1.8. Note that this rounding procedure will 
always result in an even number for the lowest-value digit.
    (5) This paragraph (e)(5) applies if the regulation specifies 
rounding to an increment other than decimal places or powers of ten (to 
the nearest 0.01, 0.1, 1, 10, 100, etc.). To round numbers for these 
special cases, divide the quantity by the specified rounding increment. 
Round the result to the nearest whole number as described in paragraphs 
(e)(1) through (4) of this section. Multiply the rounded number by the 
specified rounding increment. This value is the desired result. For 
example, to round 0.90 to the nearest 0.2, divide 0.90 by 0.2 to get a 
result of 4.5, which rounds to 4. Multiplying 4 by 0.2 gives 0.8, which 
is the result of rounding 0.90 to the nearest 0.2.
    (6) The following tables further illustrate the rounding procedures 
specified in this paragraph (e):

----------------------------------------------------------------------------------------------------------------
                                                                        Rounding increment
                    Quantity                     ---------------------------------------------------------------
                                                        10               1              0.1            0.01
----------------------------------------------------------------------------------------------------------------
3.141593........................................               0               3             3.1            3.14
123,456.789.....................................         123,460         123,457       123,456.8      123,456.79
5.500...........................................              10               6             5.5            5.50
4.500...........................................               0               4             4.5            4.50
----------------------------------------------------------------------------------------------------------------


----------------------------------------------------------------------------------------------------------------
                                                                        Rounding increment
                    Quantity                     ---------------------------------------------------------------
                                                        25               3              0.5            0.02
----------------------------------------------------------------------------------------------------------------
229.267.........................................             225             228           229.5          229.26
62.500..........................................              50              63            62.5           62.50
87.500..........................................             100              87            87.5           87.50
7.500...........................................               0               6             7.5            7.50
----------------------------------------------------------------------------------------------------------------


[[Page 59]]

    (7) This paragraph (e)(7) applies where we specify a limit or 
tolerance as some percentage of another value (such as [2% of a maximum 
concentration). You may show compliance with such specifications either 
by applying the percentage to the total value to calculate an absolute 
limit, or by converting the absolute value to a percentage by dividing 
it by the total value.
    (i) Do not round either value (the absolute limit or the calculated 
percentage), except as specified in paragraph (e)(7)(ii) of this 
section. For example, assume we specify that an analyzer must have a 
repeatability of [1% of the maximum concentration or better, the maximum 
concentration is 1059 ppm, and you determine repeatability to be [6.3 
ppm. In this example, you could calculate an absolute limit of [10.59 
ppm (1059 ppm x 0.01) or calculate that the 6.3 ppm repeatability is 
equivalent to a repeatability of 0.5949008498584%.
    (ii) Prior to July 1, 2013, you may treat tolerances (and equivalent 
specifications) specified in percentages as having fixed rather than 
infinite precision. For example, 2% would be equivalent to 1.51% to 
2.50% and 2.0% would be equivalent to 1.951% to 2.050%. Note that this 
allowance applies whether or not the percentage is explicitly specified 
as a percentage of another value.
    (8) You may use measurement devices that incorporate internal 
rounding, consistent with the provisions of this paragraph (e)(8). You 
may use devices that use any rounding convention if they report six or 
more significant digits. You may use devices that report fewer than six 
digits, consistent with good engineering judgment and the accuracy, 
repeatability, and noise specifications of this part. Note that this 
provision does not necessarily require you to perform engineering 
analysis or keep records.
    (f) Interpretation of ranges. Interpret a range as a tolerance 
unless we explicitly identify it as an accuracy, repeatability, 
linearity, or noise specification. See Sec. 1065.1001 for the 
definition of tolerance. In this part, we specify two types of ranges:
    (1) Whenever we specify a range by a single value and corresponding 
limit values above and below that value (such as X [Y), target the 
associated control point to that single value (X). Examples of this type 
of range include ``[10% of maximum pressure'', or ``(30 [10) kPa''. In 
these examples, you would target the maximum pressure or 30 kPa, 
respectively.
    (2) Whenever we specify a range by the interval between two values, 
you may target any associated control point to any value within that 
range. An example of this type of range is ``(40 to 50) kPa''.
    (g) Scaling of specifications with respect to an applicable 
standard. Because this part 1065 is applicable to a wide range of 
engines and emission standards, some of the specifications in this part 
are scaled with respect to an engine's applicable standard or maximum 
power. This ensures that the specification will be adequate to determine 
compliance, but not overly burdensome by requiring unnecessarily high-
precision equipment. Many of these specifications are given with respect 
to a ``flow-weighted mean'' that is expected at the standard or during 
testing. Flow-weighted mean is the mean of a quantity after it is 
weighted proportional to a corresponding flow rate. For example, if a 
gas concentration is measured continuously from the raw exhaust of an 
engine, its flow-weighted mean concentration is the sum of the products 
(dry-to-wet corrected, if applicable) of each recorded concentration 
times its respective exhaust flow rate, divided by the sum of the 
recorded flow rates. As another example, the bag concentration from a 
CVS system is the same as the flow-weighted mean concentration, because 
the CVS system itself flow-weights the bag concentration. Refer to Sec. 
1065.602 for information needed to estimate and calculate flow-weighted 
means. Wherever a specification is scaled to a value based upon an 
applicable standard, interpret the standard to be the family emission 
limit if the engine is certified under an emission credit program in the 
standard-setting part.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37292, June 30, 2008; 
76 FR 57438, Sept. 15, 2011; 79 FR 23753, Apr. 28, 2014]



Sec. 1065.25  Recordkeeping.

    (a) The procedures in this part include various requirements to 
record

[[Page 60]]

data or other information. Refer to the standard-setting part and Sec. 
1065.695 regarding specific recordkeeping requirements.
    (b) You must promptly send us organized, written records in English 
if we ask for them. We may review them at any time.
    (c) We may waive specific reporting or recordkeeping requirements we 
determine to be unnecessary for the purposes of this part and the 
standard-setting part. Note that while we will generally keep the 
records required by this part, we are not obligated to keep records we 
determine to be unnecessary for us to keep. For example, while we 
require you to keep records for invalid tests so that we may verify that 
your invalidation was appropriate, it is not necessary for us to keep 
records for our own invalid tests.

[79 FR 23753, Apr. 28, 2014]



                   Subpart B_Equipment Specifications



Sec. 1065.101  Overview.

    (a) This subpart specifies equipment, other than measurement 
instruments, related to emission testing. The provisions of this subpart 
apply for all engine dynamometer testing where engine speeds and loads 
are controlled to follow a prescribed duty cycle. See subpart J of this 
part to determine which of the provisions of this subpart apply for 
field testing. This equipment includes three broad categories-
dynamometers, engine fluid systems (such as fuel and intake-air 
systems), and emission-sampling hardware.
    (b) Other related subparts in this part identify measurement 
instruments (subpart C), describe how to evaluate the performance of 
these instruments (subpart D), and specify engine fluids and analytical 
gases (subpart H).
    (c) Subpart J of this part describes additional equipment that is 
specific to field testing.
    (d) Figures 1 and 2 of this section illustrate some of the possible 
configurations of laboratory equipment. These figures are schematics 
only; we do not require exact conformance to them. Figure 1 of this 
section illustrates the equipment specified in this subpart and gives 
some references to sections in this subpart. Figure 2 of this section 
illustrates some of the possible configurations of a full-flow dilution, 
constant-volume sampling (CVS) system. Not all possible CVS 
configurations are shown.
    (e) Dynamometer testing involves engine operation over speeds and 
loads that are controlled to a prescribed duty cycle. Field testing 
involves measuring emissions over normal in-use operation of a vehicle 
or piece of equipment. Field testing does not involve operating an 
engine over a prescribed duty cycle.

[[Page 61]]

[GRAPHIC] [TIFF OMITTED] TR13JY05.012


[[Page 62]]


[GRAPHIC] [TIFF OMITTED] TR13JY05.013


[70 FR 40516, July 13, 2005, as amended at 73 FR 37292, June 30, 2008]



Sec. 1065.110  Work inputs and outputs, accessory work, and operator
demand.

    (a) Work. Use good engineering judgment to simulate all engine work 
inputs and outputs as they typically would operate in use. Account for 
work inputs and outputs during an emission test by measuring them; or, 
if they are small, you may show by engineering analysis that 
disregarding them does not affect your ability to determine the net work 
output by more than [0.5% of the net expected work output over the test 
interval. Use equipment to simulate the specific types of work, as 
follows:
    (1) Shaft work. Use an engine dynamometer that is able to meet the 
cycle-validation criteria in Sec. 1065.514 over each applicable duty 
cycle.
    (i) You may use eddy-current and water-brake dynamometers for any 
testing that does not involve engine motoring, which is identified by 
negative torque commands in a reference duty cycle. See the standard 
setting part for reference duty cycles that are applicable to your 
engine.
    (ii) You may use alternating-current or direct-current motoring 
dynamometers for any type of testing.
    (iii) You may use one or more dynamometers.
    (iv) You may use any device that is already installed on a vehicle, 
equipment, or vessel to absorb work from the engine's output shaft(s). 
Examples of these types of devices include a vessel's propeller and a 
locomotive's generator.
    (2) Electrical work. Use one or more of the following to simulate 
electrical work:

[[Page 63]]

    (i) Use storage batteries or capacitors that are of the type and 
capacity installed in use.
    (ii) Use motors, generators, and alternators that are of the type 
and capacity installed in use.
    (iii) Use a resistor load bank to simulate electrical loads.
    (3) Pump, compressor, and turbine work. Use pumps, compressors, and 
turbines that are of the type and capacity installed in use. Use working 
fluids that are of the same type and thermodynamic state as normal in-
use operation.
    (b) Laboratory work inputs. You may supply any laboratory inputs of 
work to the engine. For example, you may supply electrical work to the 
engine to operate a fuel system, and as another example you may supply 
compressor work to the engine to actuate pneumatic valves. We may ask 
you to show by engineering analysis your accounting of laboratory work 
inputs to meet the criterion in paragraph (a) of this section.
    (c) Engine accessories. You must either install or account for the 
work of engine accessories required to fuel, lubricate, or heat the 
engine, circulate coolant to the engine, or to operate aftertreatment 
devices. Operate the engine with these accessories installed or 
accounted for during all testing operations, including mapping. If these 
accessories are not powered by the engine during a test, account for the 
work required to perform these functions from the total work used in 
brake-specific emission calculations. For air-cooled engines only, 
subtract externally powered fan work from total work. We may ask you to 
show by engineering analysis your accounting of engine accessories to 
meet the criterion in paragraph (a) of this section.
    (d) Engine starter. You may install a production-type starter.
    (e) Operator demand for shaft work. Operator demand is defined in 
Sec. 1065.1001. Command the operator demand and the dynamometer(s) to 
follow a prescribed duty cycle with set points for engine speed and 
torque as specified in Sec. 1065.512. Refer to the standard-setting 
part to determine the specifications for your duty cycle(s). Use a 
mechanical or electronic input to control operator demand such that the 
engine is able to meet the validation criteria in Sec. 1065.514 over 
each applicable duty cycle. Record feedback values for engine speed and 
torque as specified in Sec. 1065.512. Using good engineering judgment, 
you may improve control of operator demand by altering on-engine speed 
and torque controls. However, if these changes result in 
unrepresentative testing, you must notify us and recommend other test 
procedures under Sec. 1065.10(c)(1).
    (f) Other engine inputs. If your electronic control module requires 
specific input signals that are not available during dynamometer 
testing, such as vehicle speed or transmission signals, you may simulate 
the signals using good engineering judgment. Keep records that describe 
what signals you simulate and explain why these signals are necessary 
for representative testing.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37292, June 30, 2008]



Sec. 1065.120  Fuel properties and fuel temperature and pressure.

    (a) Use fuels as specified in the standard-setting part, or as 
specified in subpart H of this part if fuels are not specified in the 
standard-setting part.
    (b) If the engine manufacturer specifies fuel temperature and 
pressure tolerances and the location where they are to be measured, then 
measure the fuel temperature and pressure at the specified location to 
show that you are within these tolerances throughout testing.
    (c) If the engine manufacturer does not specify fuel temperature and 
pressure tolerances, use good engineering judgment to set and control 
fuel temperature and pressure in a way that represents typical in-use 
fuel temperatures and pressures.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37293, June 30, 2008]



Sec. 1065.122  Engine cooling and lubrication.

    (a) Engine cooling. Cool the engine during testing so its intake-
air, oil, coolant, block, and head temperatures are within their 
expected ranges for normal operation. You may use auxiliary coolers and 
fans.

[[Page 64]]

    (1) For air-cooled engines only, if you use auxiliary fans you must 
account for work input to the fan(s) according to Sec. 1065.110.
    (2) See Sec. 1065.125 for more information related to intake-air 
cooling.
    (3) See Sec. 1065.127 for more information related to exhaust gas 
recirculation cooling.
    (4) Measure temperatures at the manufacturer-specified locations. If 
the manufacturer does not specify temperature measurement locations, 
then use good engineering judgment to monitor intake-air, oil, coolant, 
block, and head temperatures to ensure that they are in their expected 
ranges for normal operation.
    (b) Forced cooldown. You may install a forced cooldown system for an 
engine and an exhaust aftertreatment device according to Sec. 
1065.530(a)(1).
    (c) Lubricating oil. Use lubricating oils specified in Sec. 
1065.740. For two-stroke engines that involve a specified mixture of 
fuel and lubricating oil, mix the lubricating oil with the fuel 
according to the manufacturer's specifications.
    (d) Coolant. For liquid-cooled engines, use coolant as specified in 
Sec. 1065.745.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37293, June 30, 2008]



Sec. 1065.125  Engine intake air.

    (a) Use the intake-air system installed on the engine or one that 
represents a typical in-use configuration. This includes the charge-air 
cooling and exhaust gas recirculation systems.
    (b) Measure temperature, humidity, and atmospheric pressure near the 
entrance of the furthest upstream engine or in-use intake system 
component. This would generally be near the engine's air filter, or near 
the inlet to the in-use air intake system for engines that have no air 
filter. For engines with multiple intakes, make measurements near the 
entrance of each intake.
    (1) Pressure. You may use a single shared atmospheric pressure meter 
as long as your laboratory equipment for handling intake air maintains 
ambient pressure at all intakes within [1 kPa of the shared atmospheric 
pressure. For engines with multiple intakes with separate atmospheric 
pressure measurements at each intake, use an average value for verifying 
compliance to Sec. 1065.520(b)(2).
    (2) Humidity. You may use a single shared humidity measurement for 
intake air as long as your equipment for handling intake air maintains 
dewpoint at all intakes to within [0.5  deg.C of the shared humidity 
measurement. For engines with multiple intakes with separate humidity 
measurements at each intake, use a flow-weighted average humidity for 
NOX corrections. If individual flows of each intake are not 
measured, use good engineering judgment to estimate a flow-weighted 
average humidity.
    (3) Temperature. Good engineering judgment may require that you 
shield the temperature sensors or move them upstream of an elbow in the 
laboratory intake system to prevent measurement errors due to radiant 
heating from hot engine surfaces or in-use intake system components. You 
must limit the distance between the temperature sensor and the entrance 
to the furthest upstream engine or in-use intake system component to no 
more than 12 times the outer hydraulic diameter of the entrance to the 
furthest upstream engine or in-use intake system component. However, you 
may exceed this limit if you use good engineering judgment to show that 
the temperature at the furthest upstream engine or in-use intake system 
component meets the specification in paragraph (c) of this section. For 
engines with multiple intakes, use a flow-weighted average value to 
verify compliance with the specification in paragraph (c) of this 
section. If individual flows of each intake are not measured, you may 
use good engineering judgment to estimate a flow-weighted average 
temperature. You may also verify that each individual intake complies 
with the specification in paragraph (c) of this section.
    (c) Maintain the temperature of intake air to (25 [5)  deg.C, except 
as follows:
    (1) Follow the standard-setting part if it specifies different 
temperatures.
    (2) For engines above 560 kW, you may use 35  deg.C as the upper 
bound of the tolerance. However, your system must be capable of 
controlling the temperature to the 25  deg.C setpoint for any

[[Page 65]]

steady-state operation at >30% of maximum engine power.
    (3) You may ask us to allow you to apply a different setpoint for 
intake air temperature if it is necessary to remain consistent with the 
provisions of Sec. 1065.10(c)(1) for testing during which ambient 
temperature will be outside this range.
    (d) Use an intake-air restriction that represents production 
engines. Make sure the intake-air restriction is between the 
manufacturer's specified maximum for a clean filter and the 
manufacturer's specified maximum allowed. Measure the static 
differential pressure of the restriction at the location and at the 
speed and torque set points specified by the manufacturer. If the 
manufacturer does not specify a location, measure this pressure upstream 
of any turbocharger or exhaust gas recirculation system connection to 
the intake air system. If the manufacturer does not specify speed and 
torque points, measure this pressure while the engine outputs maximum 
power. As the manufacturer, you are liable for emission compliance for 
all values up to the maximum restriction you specify for a particular 
engine.
    (e) This paragraph (e) includes provisions for simulating charge-air 
cooling in the laboratory. This approach is described in paragraph 
(e)(1) of this section. Limits on using this approach are described in 
paragraphs (e)(2) and (3) of this section.
    (1) Use a charge-air cooling system with a total intake-air capacity 
that represents production engines' in-use installation. Design any 
laboratory charge-air cooling system to minimize accumulation of 
condensate. Drain any accumulated condensate. Before starting a duty 
cycle (or preconditioning for a duty cycle), completely close all drains 
that would normally be closed during in-use operation. Keep those drains 
closed during the emission test. Maintain coolant conditions as follows:
    (i) Maintain a coolant temperature of at least 20  deg.C at the 
inlet to the charge-air cooler throughout testing. We recommend 
maintaining a coolant temperature of 25 [5  deg.C at the inlet of the 
charge-air cooler.
    (ii) At the engine conditions specified by the manufacturer, set the 
coolant flow rate to achieve an air temperature within [5  deg.C of the 
value specified by the manufacturer after the charge-air cooler's 
outlet. Measure the air-outlet temperature at the location specified by 
the manufacturer. Use this coolant flow rate set point throughout 
testing. If the engine manufacturer does not specify engine conditions 
or the corresponding charge-air cooler air outlet temperature, set the 
coolant flow rate at maximum engine power to achieve a charge-air cooler 
air outlet temperature that represents in-use operation.
    (iii) If the engine manufacturer specifies pressure-drop limits 
across the charge-air cooling system, ensure that the pressure drop 
across the charge-air cooling system at engine conditions specified by 
the manufacturer is within the manufacturer's specified limit(s). 
Measure the pressure drop at the manufacturer's specified locations.
    (2) Using a constant flow rate as described in paragraph (e)(1) of 
this section may result in unrepresentative overcooling of the intake 
air. The provisions of this paragraph (e)(2) apply instead of the 
provisions of Sec. 1065.10(c)(1) for this simulation. Our allowance to 
cool intake air as specified in this paragraph (e) does not affect your 
liability for field testing or for laboratory testing that is done in a 
way that better represents in-use operation. Where we determine that 
this allowance adversely affects your ability to demonstrate that your 
engines would comply with emission standards under in-use conditions, we 
may require you to use more sophisticated setpoints and controls of 
charge-air pressure drop, coolant temperature, and flow rate to achieve 
more representative results.
    (3) This approach does not apply for field testing. You may not 
correct measured emission levels from field testing to account for any 
differences caused by the simulated cooling in the laboratory.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37293, June 30, 2008; 
73 FR 59321, Oct. 8, 2008; 75 FR 23029, Apr. 30, 2010; 76 FR 57440, 
Sept. 15, 2011]



Sec. 1065.127  Exhaust gas recirculation.

    Use the exhaust gas recirculation (EGR) system installed with the 
engine

[[Page 66]]

or one that represents a typical in-use configuration. This includes any 
applicable EGR cooling devices.



Sec. 1065.130  Engine exhaust.

    (a) General. Use the exhaust system installed with the engine or one 
that represents a typical in-use configuration. This includes any 
applicable aftertreatment devices. We refer to exhaust piping as an 
exhaust stack; this is equivalent to a tailpipe for vehicle 
configurations.
    (b) Aftertreatment configuration. If you do not use the exhaust 
system installed with the engine, configure any aftertreatment devices 
as follows:
    (1) Position any aftertreatment device so its distance from the 
nearest exhaust manifold flange or turbocharger outlet is within the 
range specified by the engine manufacturer in the application for 
certification. If this distance is not specified, position 
aftertreatment devices to represent typical in-use vehicle 
configurations.
    (2) You may use exhaust tubing that is not from the in-use exhaust 
system upstream of any aftertreatment device that is of diameter(s) 
typical of in-use configurations. If you use exhaust tubing that is not 
from the in-use exhaust system upstream of any aftertreatment device, 
position each aftertreatment device according to paragraph (b)(1) of 
this section.
    (c) Sampling system connections. Connect an engine's exhaust system 
to any raw sampling location or dilution stage, as follows:
    (1) Minimize laboratory exhaust tubing lengths and use a total 
length of laboratory tubing of no more than 10 m or 50 outside 
diameters, whichever is greater. The start of laboratory exhaust tubing 
should be specified as the exit of the exhaust manifold, turbocharger 
outlet, last aftertreatment device, or the in-use exhaust system, 
whichever is furthest downstream. The end of laboratory exhaust tubing 
should be specified as the sample point, or first point of dilution. If 
laboratory exhaust tubing consists of several different outside tubing 
diameters, count the number of diameters of length of each individual 
diameter, then sum all the diameters to determine the total length of 
exhaust tubing in diameters. Use the mean outside diameter of any 
converging or diverging sections of tubing. Use outside hydraulic 
diameters of any noncircular sections. For multiple stack configurations 
where all the exhaust stacks are combined, the start of the laboratory 
exhaust tubing may be taken at the last joint of where all the stacks 
are combined.
    (2) You may install short sections of flexible laboratory exhaust 
tubing at any location in the engine or laboratory exhaust systems. You 
may use up to a combined total of 2 m or 10 outside diameters of 
flexible exhaust tubing.
    (3) Insulate any laboratory exhaust tubing downstream of the first 
25 outside diameters of length.
    (4) Use laboratory exhaust tubing materials that are smooth-walled, 
electrically conductive, and not reactive with exhaust constituents. 
Stainless steel is an acceptable material.
    (5) We recommend that you use laboratory exhaust tubing that has 
either a wall thickness of less than 2 mm or is air gap-insulated to 
minimize temperature differences between the wall and the exhaust.
    (6) We recommend that you connect multiple exhaust stacks from a 
single engine into one stack upstream of any emission sampling. For raw 
or dilute partial-flow emission sampling, to ensure mixing of the 
multiple exhaust streams before emission sampling, we recommend a 
minimum Reynolds number, Re #, of 4000 for the combined 
exhaust stream, whereRe # is based on the inside diameter of 
the combined flow at the first sampling point. You may configure the 
exhaust system with turbulence generators, such as orifice plates or 
fins, to achieve good mixing; inclusion of turbulence generators may be 
required forRe # less than 4000 to ensure good mixing.Re 
# is defined in Sec. 1065.640. For dilute full-flow (CVS) 
emission sampling, you may configure the exhaust system without regard 
to mixing in the laboratory section of the raw exhaust. For example you 
may size the laboratory section to reduce its pressure drop even if 
theRe #, in the laboratory section of the raw exhaust is less 
than 4000.
    (d) In-line instruments. You may insert instruments into the 
laboratory exhaust tubing, such as an in-line

[[Page 67]]

smoke meter. If you do this, you may leave a length of up to 5 outside 
diameters of laboratory exhaust tubing uninsulated on each side of each 
instrument, but you must leave a length of no more than 25 outside 
diameters of laboratory exhaust tubing uninsulated in total, including 
any lengths adjacent to in-line instruments.
    (e) Leaks. Minimize leaks sufficiently to ensure your ability to 
demonstrate compliance with the applicable standards. We recommend 
performing a chemical balance of fuel, intake air, and exhaust according 
to Sec. 1065.655 to verify exhaust system integrity.
    (f) Grounding. Electrically ground the entire exhaust system.
    (g) Forced cooldown. You may install a forced cooldown system for an 
exhaust aftertreatment device according to Sec. 1065.530(a)(1)(i).
    (h) Exhaust restriction. As the manufacturer, you are liable for 
emission compliance for all values up to the maximum restriction(s) you 
specify for a particular engine. Measure and set exhaust restriction(s) 
at the location(s) and at the engine speed and torque values specified 
by the manufacturer. Also, for variable-restriction aftertreatment 
devices, measure and set exhaust restriction(s) at the aftertreatment 
condition (degreening/aging and regeneration/loading level) specified by 
the manufacturer. If the manufacturer does not specify a location, 
measure this pressure downstream of any turbocharger. If the 
manufacturer does not specify speed and torque points, measure pressure 
while the engine produces maximum power. Use an exhaust-restriction 
setpoint that represents a typical in-use value, if available. If a 
typical in-use value for exhaust restriction is not available, set the 
exhaust restriction at (80 to 100)% of the maximum exhaust restriction 
specified by the manufacturer, or if the maximum is 5 kPa or less, the 
set point must be no less than 1.0 kPa from the maximum. For example, if 
the maximum back pressure is 4.5 kPa, do not use an exhaust restriction 
set point that is less than 3.5 kPa.
    (i) Open crankcase emissions. If the standard-setting part requires 
measuring open crankcase emissions, you may either measure open 
crankcase emissions separately using a method that we approve in 
advance, or route open crankcase emissions directly into the exhaust 
system for emission measurement. If the engine is not already configured 
to route open crankcase emissions for emission measurement, route open 
crankcase emissions as follows:
    (1) Use laboratory tubing materials that are smooth-walled, 
electrically conductive, and not reactive with crankcase emissions. 
Stainless steel is an acceptable material. Minimize tube lengths. We 
also recommend using heated or thin-walled or air gap-insulated tubing 
to minimize temperature differences between the wall and the crankcase 
emission constituents.
    (2) Minimize the number of bends in the laboratory crankcase tubing 
and maximize the radius of any unavoidable bend.
    (3) Use laboratory crankcase exhaust tubing that meets the engine 
manufacturer's specifications for crankcase back pressure.
    (4) Connect the crankcase exhaust tubing into the raw exhaust 
downstream of any aftertreatment system, downstream of any installed 
exhaust restriction, and sufficiently upstream of any sample probes to 
ensure complete mixing with the engine's exhaust before sampling. Extend 
the crankcase exhaust tube into the free stream of exhaust to avoid 
boundary-layer effects and to promote mixing. You may orient the 
crankcase exhaust tube's outlet in any direction relative to the raw 
exhaust flow.

[73 FR 37293, June 30, 2008, as amended at 79 FR 23754, Apr. 28, 2014]



Sec. 1065.140  Dilution for gaseous and PM constituents.

    (a) General. You may dilute exhaust with ambient air, purified air, 
or nitrogen. References in this part to ``dilution air'' may include any 
of these. For gaseous emission measurement, the dilution air must be at 
least 15  deg.C. Note that the composition of the dilution air affects 
some gaseous emission measurement instruments' response to emissions. We 
recommend diluting exhaust at a location as close as possible

[[Page 68]]

to the location where ambient air dilution would occur in use. Dilution 
may occur in a single stage or in multiple stages. For dilution in 
multiple stages, the first stage is considered primary dilution and 
later stages are considered secondary dilution.
    (b) Dilution-air conditions and background concentrations. Before 
dilution air is mixed with exhaust, you may precondition it by 
increasing or decreasing its temperature or humidity. You may also 
remove constituents to reduce their background concentrations. The 
following provisions apply to removing constituents or accounting for 
background concentrations:
    (1) You may measure constituent concentrations in the dilution air 
and compensate for background effects on test results. See Sec. 
1065.650 for calculations that compensate for background concentrations 
(40 CFR 1066.610 for vehicle testing).
    (2) Measure these background concentrations the same way you measure 
diluted exhaust constituents, or measure them in a way that does not 
affect your ability to demonstrate compliance with the applicable 
standards. For example, you may use the following simplifications for 
background sampling:
    (i) You may disregard any proportional sampling requirements.
    (ii) You may use unheated gaseous sampling systems.
    (iii) You may use unheated PM sampling systems.
    (iv) You may use continuous sampling if you use batch sampling for 
diluted emissions.
    (v) You may use batch sampling if you use continuous sampling for 
diluted emissions.
    (3) For removing background PM, we recommend that you filter all 
dilution air, including primary full-flow dilution air, with high-
efficiency particulate air (HEPA) filters that have an initial minimum 
collection efficiency specification of 99.97% (see Sec. 1065.1001 for 
procedures related to HEPA-filtration efficiencies). Ensure that HEPA 
filters are installed properly so that background PM does not leak past 
the HEPA filters. If you choose to correct for background PM without 
using HEPA filtration, demonstrate that the background PM in the 
dilution air contributes less than 50% to the net PM collected on the 
sample filter. You may correct net PM without restriction if you use 
HEPA filtration.
    (c) Full-flow dilution; constant-volume sampling (CVS). You may 
dilute the full flow of raw exhaust in a dilution tunnel that maintains 
a nominally constant volume flow rate, molar flow rate or mass flow rate 
of diluted exhaust, as follows:
    (1) Construction. Use a tunnel with inside surfaces of 300 series 
stainless steel. Electrically ground the entire dilution tunnel. We 
recommend a thin-walled and insulated dilution tunnel to minimize 
temperature differences between the wall and the exhaust gases. You may 
not use any flexible tubing in the dilution tunnel upstream of the PM 
sample probe. You may use nonconductive flexible tubing downstream of 
the PM sample probe and upstream of the CVS flow meter; use good 
engineering judgment to select a tubing material that is not prone to 
leaks, and configure the tubing to ensure smooth flow at the CVS flow 
meter.
    (2) Pressure control. Maintain static pressure at the location where 
raw exhaust is introduced into the tunnel within [1.2 kPa of atmospheric 
pressure. You may use a booster blower to control this pressure. If you 
test using more careful pressure control and you show by engineering 
analysis or by test data that you require this level of control to 
demonstrate compliance at the applicable standards, we will maintain the 
same level of static pressure control when we test.
    (3) Mixing. Introduce raw exhaust into the tunnel by directing it 
downstream along the centerline of the tunnel. If you dilute directly 
from the exhaust stack, the end of the exhaust stack is considered to be 
the start of the dilution tunnel. You may introduce a fraction of 
dilution air radially from the tunnel's inner surface to minimize 
exhaust interaction with the tunnel walls. You may configure the system 
with turbulence generators such as orifice plates or fins to achieve 
good mixing. We recommend a minimum Reynolds number, Re #, of 
4000 for the diluted exhaust stream, whereRe # is

[[Page 69]]

based on the inside diameter of the dilution tunnel. Re # is 
defined in Sec. 1065.640.
    (4) Flow measurement preconditioning. You may condition the diluted 
exhaust before measuring its flow rate, as long as this conditioning 
takes place downstream of any heated HC or PM sample probes, as follows:
    (i) You may use flow straighteners, pulsation dampeners, or both of 
these.
    (ii) You may use a filter.
    (iii) You may use a heat exchanger to control the temperature 
upstream of any flow meter, but you must take steps to prevent aqueous 
condensation as described in paragraph (c)(6) of this section.
    (5) Flow measurement. Section 1065.240 describes measurement 
instruments for diluted exhaust flow.
    (6) Aqueous condensation. This paragraph (c)(6) describes how you 
must address aqueous condensation in the CVS. As described below, you 
may meet these requirements by preventing or limiting aqueous 
condensation in the CVS from the exhaust inlet to the last emission 
sample probe. See that paragraph for provisions related to the CVS 
between the last emission sample probe and the CVS flow meter. You may 
heat and/or insulate the dilution tunnel walls, as well as the bulk 
stream tubing downstream of the tunnel to prevent or limit aqueous 
condensation. Where we allow aqueous condensation to occur, use good 
engineering judgment to ensure that the condensation does not affect 
your ability to demonstrate that your engines comply with the applicable 
standards (see Sec. 1065.10(a)).
    (i) Preventing aqueous condensation. To prevent condensation, you 
must keep the temperature of internal surfaces, excluding any sample 
probes, above the dew point of the dilute exhaust passing through the 
CVS tunnel. Use good engineering judgment to monitor temperatures in the 
CVS. For the purposes of this paragraph (c)(6), assume that aqueous 
condensation is pure water condensate only, even though the definition 
of ``aqueous condensation'' in Sec. 1065.1001 includes condensation of 
any constituents that contain water. No specific verification check is 
required under this paragraph (c)(6)(i), but we may ask you to show how 
you comply with this requirement. You may use engineering analysis, CVS 
tunnel design, alarm systems, measurements of wall temperatures, and 
calculation of water dew point to demonstrate compliance with this 
requirement. For optional CVS heat exchangers, you may use the lowest 
water temperature at the inlet(s) and outlet(s) to determine the minimum 
internal surface temperature.
    (ii) Limiting aqueous condensation. This paragraph (c)(6)(ii) 
specifies limits of allowable condensation and requires you to verify 
that the amount of condensation that occurs during each test interval 
does not exceed the specified limits.
    (A) Use chemical balance equations in Sec. 1065.655 to calculate 
the mole fraction of water in the dilute exhaust continuously during 
testing. Alternatively, you may continuously measure the mole fraction 
of water in the dilute exhaust prior to any condensation during testing. 
Use good engineering judgment to select, calibrate and verify water 
analyzers/detectors. The linearity verification requirements of Sec. 
1065.307 do not apply to water analyzers/detectors used to correct for 
the water content in exhaust samples.
    (B) Use good engineering judgment to select and monitor locations on 
the CVS tunnel walls prior to the last emission sample probe. If you are 
also verifying limited condensation from the last emission sample probe 
to the CVS flow meter, use good engineering judgment to select and 
monitor locations on the CVS tunnel walls, optional CVS heat exchanger, 
and CVS flow meter. For optional CVS heat exchangers, you may use the 
lowest water temperature at the inlet(s) and outlet(s) to determine the 
minimum internal surface temperature. Identify the minimum surface 
temperature on a continuous basis.
    (C) Identify the maximum potential mole fraction of dilute exhaust 
lost on a continuous basis during the entire test interval. This value 
must be less than or equal to 0.02. Calculate on a continuous basis the 
mole fraction of water that would be in equilibrium with liquid water at 
the measured minimum surface temperature. Subtract

[[Page 70]]

this mole fraction from the mole fraction of water that would be in the 
exhaust without condensation (either measured or from the chemical 
balance), and set any negative values to zero. This difference is the 
potential mole fraction of the dilute exhaust that would be lost due to 
water condensation on a continuous basis.
    (D) Integrate the product of the molar flow rate of the dilute 
exhaust and the potential mole fraction of dilute exhaust lost, and 
divide by the totalized dilute exhaust molar flow over the test 
interval. This is the potential mole fraction of the dilute exhaust that 
would be lost due to water condensation over the entire test interval. 
Note that this assumes no re-evaporation. This value must be less than 
or equal to 0.005.
    (7) Flow compensation. Maintain nominally constant molar, volumetric 
or mass flow of diluted exhaust. You may maintain nominally constant 
flow by either maintaining the temperature and pressure at the flow 
meter or by directly controlling the flow of diluted exhaust. You may 
also directly control the flow of proportional samplers to maintain 
proportional sampling. For an individual test, verify proportional 
sampling as described in Sec. 1065.545.
    (d) Partial-flow dilution (PFD). You may dilute a partial flow of 
raw or previously diluted exhaust before measuring emissions. Section 
1065.240 describes PFD-related flow measurement instruments. PFD may 
consist of constant or varying dilution ratios as described in 
paragraphs (d)(2) and (3) of this section. An example of a constant 
dilution ratio PFD is a ``secondary dilution PM'' measurement system.
    (1) Applicability. (i) You may use PFD to extract a proportional raw 
exhaust sample for any batch or continuous PM emission sampling over any 
transient duty cycle, any steady-state duty cycle, or any ramped-modal 
cycle.
    (ii) You may use PFD to extract a proportional raw exhaust sample 
for any batch or continuous gaseous emission sampling over any transient 
duty cycle, any steady-state duty cycle, or any ramped-modal cycle.
    (iii) You may use PFD to extract a proportional raw exhaust sample 
for any batch or continuous field-testing.
    (iv) You may use PFD to extract a proportional diluted exhaust 
sample from a CVS for any batch or continuous emission sampling.
    (v) You may use PFD to extract a constant raw or diluted exhaust 
sample for any continuous emission sampling.
    (vi) You may use PFD to extract a constant raw or diluted exhaust 
sample for any steady-state emission sampling.
    (2) Constant dilution-ratio PFD. Do one of the following for 
constant dilution-ratio PFD:
    (i) Dilute an already proportional flow. For example, you may do 
this as a way of performing secondary dilution from a CVS tunnel to 
achieve overall dilution ratio for PM sampling.
    (ii) Continuously measure constituent concentrations. For example, 
you might dilute to precondition a sample of raw exhaust to control its 
temperature, humidity, or constituent concentrations upstream of 
continuous analyzers. In this case, you must take into account the 
dilution ratio before multiplying the continuous concentration by the 
sampled exhaust flow rate.
    (iii) Extract a proportional sample from a separate constant 
dilution ratio PFD system. For example, you might use a variable-flow 
pump to proportionally fill a gaseous storage medium such as a bag from 
a PFD system. In this case, the proportional sampling must meet the same 
specifications as varying dilution ratio PFD in paragraph (d)(3) of this 
section.
    (iv) For each mode of a discrete-mode test (such as a locomotive 
notch setting or a specific setting for speed and torque), use a 
constant dilution ratio for any PM sampling. You must change the overall 
PM sampling system dilution ratio between modes so that the dilution 
ratio on the mode with the highest exhaust flow rate meets Sec. 
1065.140(e)(2) and the dilution ratios on all other modes is higher than 
this (minimum) dilution ratio by the ratio of the maximum exhaust flow 
rate to the exhaust flow rate of the corresponding other mode. This is 
the same dilution ratio requirement for RMC or field transient testing. 
You must account for this change in dilution ratio in your emission 
calculations.

[[Page 71]]

    (3) Varying dilution-ratio PFD. All the following provisions apply 
for varying dilution-ratio PFD:
    (i) Use a control system with sensors and actuators that can 
maintain proportional sampling over intervals as short as 200 ms (i.e., 
5 Hz control).
    (ii) For control input, you may use any sensor output from one or 
more measurements; for example, intake-air flow, fuel flow, exhaust 
flow, engine speed, and intake manifold temperature and pressure.
    (iii) Account for any emission transit time in the PFD system, as 
necessary.
    (iv) You may use preprogrammed data if they have been determined for 
the specific test site, duty cycle, and test engine from which you 
dilute emissions.
    (v) We recommend that you run practice cycles to meet the 
verification criteria in Sec. 1065.545. Note that you must verify every 
emission test by meeting the verification criteria with the data from 
that specific test. Data from previously verified practice cycles or 
other tests may not be used to verify a different emission test.
    (vi) You may not use a PFD system that requires preparatory tuning 
or calibration with a CVS or with the emission results from a CVS. 
Rather, you must be able to independently calibrate the PFD.
    (e) Dilution air temperature, dilution ratio, residence time, and 
temperature control of PM samples. Dilute PM samples at least once 
upstream of transfer lines. You may dilute PM samples upstream of a 
transfer line using full-flow dilution, or partial-flow dilution 
immediately downstream of a PM probe. In the case of partial-flow 
dilution, you may have up to 26 cm of insulated length between the end 
of the probe and the dilution stage, but we recommend that the length be 
as short as practical. The intent of these specifications is to minimize 
heat transfer to or from the emission sample before the final stage of 
dilution, other than the heat you may need to add to prevent aqueous 
condensation. This is accomplished by initially cooling the sample 
through dilution. Configure dilution systems as follows:
    (1) Set the dilution air temperature to (25 [5)  deg.C. Use good 
engineering judgment to select a location to measure this temperature 
that is as close as practical upstream of the point where dilution air 
mixes with raw exhaust.
    (2) For any PM dilution system (i.e., CVS or PFD), add dilution air 
to the raw exhaust such that the minimum overall ratio of diluted 
exhaust to raw exhaust is within the range of (5:1 to 7:1) and is at 
least 2:1 for any primary dilution stage. Base this minimum value on the 
maximum engine exhaust flow rate for a given test interval. Either 
measure the maximum exhaust flow during a practice run of the test 
interval or estimate it based on good engineering judgment (for example, 
you might rely on manufacturer-published literature).
    (3) Configure any PM dilution system to have an overall residence 
time of (1.0 to 5.5) s, as measured from the location of initial 
dilution air introduction to the location where PM is collected on the 
sample media. Also configure the system to have a residence time of at 
least 0.50 s, as measured from the location of final dilution air 
introduction to the location where PM is collected on the sample media. 
When determining residence times within sampling system volumes, use an 
assumed flow temperature of 25  deg.C and pressure of 101.325 kPa.
    (4) Control sample temperature to a (47 [5)  deg.C tolerance, as 
measured anywhere within 20 cm upstream or downstream of the PM storage 
media (such as a filter). Measure this temperature with a bare-wire 
junction thermocouple with wires that are (0.500 [0.025) mm diameter, or 
with another suitable instrument that has equivalent performance.

[79 FR 23754, Apr. 28, 2014, as amended at 81 FR 74162, Oct. 25, 2016]



Sec. 1065.145  Gaseous and PM probes, transfer lines, and sampling
system components.

    (a) Continuous and batch sampling. Determine the total mass of each 
constituent with continuous or batch sampling. Both types of sampling 
systems have probes, transfer lines, and other sampling system 
components that are described in this section.
    (b) Options for engines with multiple exhaust stacks. Measure 
emissions from

[[Page 72]]

a test engine as described in this paragraph (b) if it has multiple 
exhaust stacks. You may choose to use different measurement procedures 
for different pollutants under this paragraph (b) for a given test. For 
purposes of this part 1065, the test engine includes all the devices 
related to converting the chemical energy in the fuel to the engine's 
mechanical output energy. This may or may not involve vehicle- or 
equipment-based devices. For example, all of an engine's cylinders are 
considered to be part of the test engine even if the exhaust is divided 
into separate exhaust stacks. As another example, all the cylinders of a 
diesel-electric locomotive are considered to be part of the test engine 
even if they transmit power through separate output shafts, such as 
might occur with multiple engine-generator sets working in tandem. Use 
one of the following procedures to measure emissions with multiple 
exhaust stacks:
    (1) Route the exhaust flow from the multiple stacks into a single 
flow as described in Sec. 1065.130(c)(6). Sample and measure emissions 
after the exhaust streams are mixed. Calculate the emissions as a single 
sample from the entire engine. We recommend this as the preferred 
option, since it requires only a single measurement and calculation of 
the exhaust molar flow for the entire engine.
    (2) Sample and measure emissions from each stack and calculate 
emissions separately for each stack. Add the mass (or mass rate) 
emissions from each stack to calculate the emissions from the entire 
engine. Testing under this paragraph (b)(2) requires measuring or 
calculating the exhaust molar flow for each stack separately. If the 
exhaust molar flow in each stack cannot be calculated from combustion 
air flow(s), fuel flow(s), and measured gaseous emissions, and it is 
impractical to measure the exhaust molar flows directly, you may 
alternatively proportion the engine's calculated total exhaust molar 
flow rate (where the flow is calculated using combustion air mass 
flow(s), fuel mass flow(s), and emissions concentrations) based on 
exhaust molar flow measurements in each stack using a less accurate, 
non-traceable method. For example, you may use a total pressure probe 
and static pressure measurement in each stack.
    (3) Sample and measure emissions from one stack and repeat the duty 
cycle as needed to collect emissions from each stack separately. 
Calculate the emissions from each stack and add the separate 
measurements to calculate the mass (or mass rate) emissions from the 
entire engine. Testing under this paragraph (b)(3) requires measuring or 
calculating the exhaust molar flow for each stack separately. You may 
alternatively proportion the engine's calculated total exhaust molar 
flow rate based on calculation and measurement limitations as described 
in paragraph (b)(2) of this section. Use the average of the engine's 
total power or work values from the multiple test runs to calculate 
brake-specific emissions. Divide the total mass (or mass rate) of each 
emission by the average power (or work). You may alternatively use the 
engine power or work associated with the corresponding stack during each 
test run if these values can be determined for each stack separately.
    (4) Sample and measure emissions from each stack separately and 
calculate emissions for the entire engine based on the stack with the 
highest concentration. Testing under this paragraph (b)(4) requires only 
a single exhaust flow measurement or calculation for the entire engine. 
You may determine which stack has the highest concentration by 
performing multiple test runs, reviewing the results of earlier tests, 
or using good engineering judgment. Note that the highest concentration 
of different pollutants may occur in different stacks. Note also that 
the stack with the highest concentration of a pollutant during a test 
interval for field testing may be a different stack than the one you 
identified based on average concentrations over a duty cycle.
    (5) Sample emissions from each stack separately and combine the wet 
sample streams from each stack proportionally to the exhaust molar flows 
in each stack. Measure the emission concentrations and calculate the 
emissions for the entire engine based on these weighted concentrations. 
Testing

[[Page 73]]

under this paragraph (b)(5) requires measuring or calculating the 
exhaust molar flow for each stack separately during the test run to 
proportion the sample streams from each stack. If it is impractical to 
measure the exhaust molar flows directly, you may alternatively 
proportion the wet sample streams based on less accurate, non-traceable 
flow methods. For example, you may use a total pressure probe and static 
pressure measurement in each stack. The following restrictions apply for 
testing under this paragraph (b)(5):
    (i) You must use an accurate, traceable measurement or calculation 
of the engine's total exhaust molar flow rate for calculating the mass 
of emissions from the entire engine.
    (ii) You may dry the single, combined, proportional sample stream; 
you may not dry the sample streams from each stack separately.
    (iii) You must measure and proportion the sample flows from each 
stack with active flow controls. For PM sampling, you must measure and 
proportion the diluted sample flows from each stack with active flow 
controls that use only smooth walls with no sudden change in cross-
sectional area. For example, you may control the dilute exhaust PM 
sample flows using electrically conductive vinyl tubing and a control 
device that pinches the tube over a long enough transition length so no 
flow separation occurs.
    (iv) For PM sampling, the transfer lines from each stack must be 
joined so the angle of the joining flows is 12.5 deg. or less. Note that 
the exhaust manifold must meet the same specifications as the transfer 
line according to paragraph (d) of this section.
    (6) Sample emissions from each stack separately and combine the wet 
sample streams from each stack equally. Measure the emission 
concentrations and calculate the emissions for the entire engine based 
on these measured concentrations. Testing under this paragraph (b)(6) 
assumes that the raw-exhaust and sample flows are the same for each 
stack. The following restrictions apply for testing under this paragraph 
(b)(6):
    (i) You must measure and demonstrate that the sample flow from each 
stack is within 5% of the value from the stack with the highest sample 
flow. You may alternatively ensure that the stacks have equal flow rates 
without measuring sample flows by designing a passive sampling system 
that meets the following requirements:
    (A) The probes and transfer line branches must be symmetrical, have 
equal lengths and diameters, have the same number of bends, and have no 
filters.
    (B) If probes are designed such that they are sensitive to stack 
velocity, the stack velocity must be similar at each probe. For example, 
a static pressure probe used for gaseous sampling is not sensitive to 
stack velocity.
    (C) The stack static pressure must be the same at each probe. You 
can meet this requirement by placing probes at the end of stacks that 
are vented to atmosphere.
    (D) For PM sampling, the transfer lines from each stack must be 
joined so the angle of the joining flows is 12.5 deg. or less. Note that 
the exhaust manifold must meet the same specifications as the transfer 
line according to paragraph (d) of this section.
    (ii) You may use the procedure in this paragraph (b)(6) only if you 
perform an analysis showing that the resulting error due to imbalanced 
stack flows and concentrations is either at or below 2%. You may 
alternatively show that the resulting error does not impact your ability 
to demonstrate compliance with applicable standards. For example, you 
may use less accurate, non-traceable measurements of emission 
concentrations and molar flow in each stack and demonstrate that the 
imbalances in flows and concentrations cause 2% or less error.
    (iii) For a two-stack engine, you may use the procedure in this 
paragraph (b)(6) only if you can show that the stack with the higher 
flow has the lower average concentration for each pollutant over the 
duty cycle.
    (iv) You must use an accurate, traceable measurement or calculation 
of the engine's total exhaust molar flow rate for calculating the mass 
of emissions from the entire engine.
    (v) You may dry the single, equally combined, sample stream; you may 
not dry the sample streams from each stack separately.

[[Page 74]]

    (vi) You may determine your exhaust flow rates with a chemical 
balance of exhaust gas concentrations and either intake air flow or fuel 
flow.
    (c) Gaseous and PM sample probes. A probe is the first fitting in a 
sampling system. It protrudes into a raw or diluted exhaust stream to 
extract a sample, such that its inside and outside surfaces are in 
contact with the exhaust. A sample is transported out of a probe into a 
transfer line, as described in paragraph (d) of this section. The 
following provisions apply to sample probes:
    (1) Probe design and construction. Use sample probes with inside 
surfaces of 300 series stainless steel or, for raw exhaust sampling, use 
any nonreactive material capable of withstanding raw exhaust 
temperatures. Locate sample probes where constituents are mixed to their 
mean sample concentration. Take into account the mixing of any crankcase 
emissions that may be routed into the raw exhaust. Locate each probe to 
minimize interference with the flow to other probes. We recommend that 
all probes remain free from influences of boundary layers, wakes, and 
eddies--especially near the outlet of a raw-exhaust stack where 
unintended dilution might occur. Make sure that purging or back-flushing 
of a probe does not influence another probe during testing. You may use 
a single probe to extract a sample of more than one constituent as long 
as the probe meets all the specifications for each constituent.
    (2) Gaseous sample probes. Use either single-port or multi-port 
probes for sampling gaseous emissions. You may orient these probes in 
any direction relative to the raw or diluted exhaust flow. For some 
probes, you must control sample temperatures, as follows:
    (i) For probes that extract NOX from diluted exhaust, 
control the probe's wall temperature to prevent aqueous condensation.
    (ii) For probes that extract hydrocarbons for THC or NMHC analysis 
from the diluted exhaust of compression-ignition engines, two-stroke 
spark-ignition engines, or four-stroke spark-ignition engines at or 
below 19 kW, we recommend heating the probe to minimize hydrocarbon 
contamination consistent with good engineering judgment. If you 
routinely fail the contamination check in the 1065.520 pretest check, we 
recommend heating the probe section to approximately 190  deg.C to 
minimize contamination.
    (3) PM sample probes. Use PM probes with a single opening at the 
end. Orient PM probes to face directly upstream. If you shield a PM 
probe's opening with a PM pre-classifier such as a hat, you may not use 
the preclassifier we specify in paragraph (f)(1) of this section. We 
recommend sizing the inside diameter of PM probes to approximate 
isokinetic sampling at the expected mean flow rate.
    (d) Transfer lines. You may use transfer lines to transport an 
extracted sample from a probe to an analyzer, storage medium, or 
dilution system, noting certain restrictions for PM sampling in Sec. 
1065.140(e). Minimize the length of all transfer lines by locating 
analyzers, storage media, and dilution systems as close to probes as 
practical. We recommend that you minimize the number of bends in 
transfer lines and that you maximize the radius of any unavoidable bend. 
Avoid using 90 deg. elbows, tees, and cross-fittings in transfer lines. 
Where such connections and fittings are necessary, take steps, using 
good engineering judgment, to ensure that you meet the temperature 
tolerances in this paragraph (d). This may involve measuring temperature 
at various locations within transfer lines and fittings. You may use a 
single transfer line to transport a sample of more than one constituent, 
as long as the transfer line meets all the specifications for each 
constituent. The following construction and temperature tolerances apply 
to transfer lines:
    (1) Gaseous samples. Use transfer lines with inside surfaces of 300 
series stainless steel, PTFE, Viton \TM\, or any other material that you 
demonstrate has better properties for emission sampling. For raw exhaust 
sampling, use a non-reactive material capable of withstanding raw 
exhaust temperatures. You may use in-line filters if they do not react 
with exhaust constituents and if the filter and its housing meet the 
same temperature requirements as the transfer lines, as follows:
    (i) For NOX transfer lines upstream of either an 
NO2-to-NO converter that

[[Page 75]]

meets the specifications of Sec. 1065.378 or a chiller that meets the 
specifications of Sec. 1065.376, maintain a sample temperature that 
prevents aqueous condensation.
    (ii) For THC transfer lines for testing compression-ignition 
engines, two-stroke spark-ignition engines, or four-stroke spark-
ignition engines at or below 19 kW, maintain a wall temperature 
tolerance throughout the entire line of (191 [11)  deg.C. If you sample 
from raw exhaust, you may connect an unheated, insulated transfer line 
directly to a probe. Design the length and insulation of the transfer 
line to cool the highest expected raw exhaust temperature to no lower 
than 191  deg.C, as measured at the transfer line's outlet. For dilute 
sampling, you may use a transition zone between the probe and transfer 
line of up to 92 cm to allow your wall temperature to transition to (191 
[11)  deg.C.
    (2) PM samples. We recommend heated transfer lines or a heated 
enclosure to minimize temperature differences between transfer lines and 
exhaust constituents. Use transfer lines that are inert with respect to 
PM and are electrically conductive on the inside surfaces. We recommend 
using PM transfer lines made of 300 series stainless steel. Electrically 
ground the inside surface of PM transfer lines.
    (e) Optional sample-conditioning components for gaseous sampling. 
You may use the following sample-conditioning components to prepare 
gaseous samples for analysis, as long as you do not install or use them 
in a way that adversely affects your ability to show that your engines 
comply with all applicable gaseous emission standards.
    (1) NO2-to-NO converter. You may use an NO2-to-NO 
converter that meets the converter conversion verification specified in 
Sec. 1065.378 at any point upstream of a NOX analyzer, 
sample bag, or other storage medium.
    (2) Sample dryer. You may use either type of sample dryer described 
in this paragraph (e)(2) to decrease the effects of water on gaseous 
emission measurements. You may not use a chemical dryer, or use dryers 
upstream of PM sample filters.
    (i) Osmotic-membrane. You may use an osmotic-membrane dryer upstream 
of any gaseous analyzer or storage medium, as long as it meets the 
temperature specifications in paragraph (d)(1) of this section. Because 
osmotic-membrane dryers may deteriorate after prolonged exposure to 
certain exhaust constituents, consult with the membrane manufacturer 
regarding your application before incorporating an osmotic-membrane 
dryer. Monitor the dewpoint, Tdew, and absolute pressure, 
ptotal, downstream of an osmotic-membrane dryer. You may use 
continuously recorded values of Tdew and ptotal in 
the amount of water calculations specified in Sec. 1065.645. For our 
testing we may use average temperature and pressure values over the test 
interval or a nominal pressure value that we estimate as the dryer's 
average pressure expected during testing as constant values in the 
amount of water calculations specified in Sec. 1065.645. For your 
testing, you may use the maximum temperature or minimum pressure values 
observed during a test interval or duty cycle or the high alarm 
temperature setpoint or low alarm pressure setpoint as constant values 
in the calculations specified in Sec. 1065.645. For your testing, you 
may also use a nominal ptotal, which you may estimate as the 
dryer's lowest absolute pressure expected during testing.
    (ii) Thermal chiller. You may use a thermal chiller upstream of some 
gas analyzers and storage media. You may not use a thermal chiller 
upstream of a THC measurement system for compression-ignition engines, 
two-stroke spark-ignition engines, or four-stroke spark-ignition engines 
at or below 19 kW. If you use a thermal chiller upstream of an 
NO2-to-NO converter or in a sampling system without an 
NO2-to-NO converter, the chiller must meet the NO2 
loss-performance check specified in Sec. 1065.376. Monitor the 
dewpoint, Tdew, and absolute pressure, p total, 
downstream of a thermal chiller. You may use continuously recorded 
values of Tdew and ptotal in the amount of water 
calculations specified in Sec. 1065.645. If it is valid to assume the 
degree of saturation in the thermal chiller, you may calculate T 
dew based on the known chiller performance and continuous 
monitoring of chiller temperature,

[[Page 76]]

Tchiller. If it is valid to assume a constant temperature 
offset between Tchiller and Tdew, due to a known 
and fixed amount of sample reheat between the chiller outlet and the 
temperature measurement location, you may factor in this assumed 
temperature offset value into emission calculations. If we ask for it, 
you must show by engineering analysis or by data the validity of any 
assumptions allowed by this paragraph (e)(2)(ii). For our testing we may 
use average temperature and pressure values over the test interval or a 
nominal pressure value that we estimate as the dryer's average pressure 
expected during testing as constant values in the calculations specified 
in Sec. 1065.645. For your testing you may use the maximum temperature 
and minimum pressure values observed during a test interval or duty 
cycle or the high alarm temperature setpoint and the low alarm pressure 
setpoint as constant values in the amount of water calculations 
specified in Sec. 1065.645. For your testing you may also use a nominal 
ptotal, which you may estimate as the dryer's lowest absolute 
pressure expected during testing.
    (3) Sample pumps. You may use sample pumps upstream of an analyzer 
or storage medium for any gas. Use sample pumps with inside surfaces of 
300 series stainless steel, PTFE, or any other material that you 
demonstrate has better properties for emission sampling. For some sample 
pumps, you must control temperatures, as follows:
    (i) If you use a NOX sample pump upstream of either an 
NO2-to-NO converter that meets Sec. 1065.378 or a chiller 
that meets Sec. 1065.376, it must be heated to prevent aqueous 
condensation.
    (ii) For testing compression-ignition engines, two-stroke spark-
ignition engines, or four-stroke spark-ignition engines at or below 19 
kW, if you use a THC sample pump upstream of a THC analyzer or storage 
medium, its inner surfaces must be heated to a tolerance of (191 [11) 
deg.C.
    (4) Ammonia Scrubber. You may use ammonia scrubbers for any or all 
gaseous sampling systems to prevent interference with NH3, 
poisoning of the NO2-to-NO converter, and deposits in the 
sampling system or analyzers. Follow the ammonia scrubber manufacturer's 
recommendations or use good engineering judgment in applying ammonia 
scrubbers.
    (f) Optional sample-conditioning components for PM sampling. You may 
use the following sample-conditioning components to prepare PM samples 
for analysis, as long as you do not install or use them in a way that 
adversely affects your ability to show that your engines comply with the 
applicable PM emission standards. You may condition PM samples to 
minimize positive and negative biases to PM results, as follows:
    (1) PM preclassifier. You may use a PM preclassifier to remove 
large-diameter particles. The PM preclassifier may be either an inertial 
impactor or a cyclonic separator. It must be constructed of 300 series 
stainless steel. The preclassifier must be rated to remove at least 50% 
of PM at an aerodynamic diameter of 10 [micro] m and no more than 1% of 
PM at an aerodynamic diameter of 1 [micro] m over the range of flow 
rates for which you use it. Follow the preclassifier manufacturer's 
instructions for any periodic servicing that may be necessary to prevent 
a buildup of PM. Install the preclassifier in the dilution system 
downstream of the last dilution stage. Configure the preclassifier 
outlet with a means of bypassing any PM sample media so the 
preclassifier flow may be stabilized before starting a test. Locate PM 
sample media within 75 cm downstream of the preclassifier's exit. You 
may not use this preclassifier if you use a PM probe that already has a 
preclassifier. For example, if you use a hat-shaped preclassifier that 
is located immediately upstream of the probe in such a way that it 
forces the sample flow to change direction before entering the probe, 
you may not use any other preclassifier in your PM sampling system.
    (2) Other components. You may request to use other PM conditioning 
components upstream of a PM preclassifier, such as components that 
condition humidity or remove gaseous-phase hydrocarbons from the diluted 
exhaust stream. You may use such

[[Page 77]]

components only if we approve them under Sec. 1065.10.

[75 FR 23030, Apr. 30, 2010; 79 FR 23756, Apr. 28, 2014]



Sec. 1065.150  Continuous sampling.

    You may use continuous sampling techniques for measurements that 
involve raw or dilute sampling. Make sure continuous sampling systems 
meet the specifications in Sec. 1065.145. Make sure continuous 
analyzers meet the specifications in subparts C and D of this part.



Sec. 1065.170  Batch sampling for gaseous and PM constituents.

    Batch sampling involves collecting and storing emissions for later 
analysis. Examples of batch sampling include collecting and storing 
gaseous emissions in a bag or collecting and storing PM on a filter. You 
may use batch sampling to store emissions that have been diluted at 
least once in some way, such as with CVS, PFD, or BMD. You may use 
batch-sampling to store undiluted emissions.
    (a) Sampling methods. If you extract from a constant-volume flow 
rate, sample at a constant-volume flow rate as follows:
    (1) Verify proportional sampling after an emission test as described 
in Sec. 1065.545. Use good engineering judgment to select storage media 
that will not significantly change measured emission levels (either up 
or down). For example, do not use sample bags for storing emissions if 
the bags are permeable with respect to emissions or if they off gas 
emissions to the extent that it affects your ability to demonstrate 
compliance with the applicable gaseous emission standards. As another 
example, do not use PM filters that irreversibly absorb or adsorb gases 
to the extent that it affects your ability to demonstrate compliance 
with the applicable PM emission standard.
    (2) You must follow the requirements in Sec. 1065.140(e)(2) related 
to PM dilution ratios. For each filter, if you expect the net PM mass on 
the filter to exceed 400 [micro] g, assuming a 38 mm diameter filter 
stain area, you may take the following actions in sequence:
    (i) For discrete-mode testing only, you may reduce sample time as 
needed to target a filter loading of 400 [micro] g, but not below the 
minimum sample time specified in the standard-setting part.
    (ii) Reduce filter face velocity as needed to target a filter 
loading of 400 [micro] g, down to 50 cm/s or less.
    (iii) Increase overall dilution ratio above the values specified in 
Sec. 1065.140(e)(2) to target a filter loading of 400 [micro] g.
    (b) Gaseous sample storage media. Store gas volumes in sufficiently 
clean containers that minimally off-gas or allow permeation of gases. 
Use good engineering judgment to determine acceptable thresholds of 
storage media cleanliness and permeation. To clean a container, you may 
repeatedly purge and evacuate a container and you may heat it. Use a 
flexible container (such as a bag) within a temperature-controlled 
environment, or use a temperature controlled rigid container that is 
initially evacuated or has a volume that can be displaced, such as a 
piston and cylinder arrangement. Use containers meeting the 
specifications in the Table 1 of this section, noting that you may 
request to use other container materials under Sec. 1065.10. Sample 
temperatures must stay within the following ranges for each container 
material:
    (1) Up to 40  deg.C for Tedlar \TM\ and Kynar \TM\..
    (2) (191 [11)  deg.C for Teflon \TM\ and 300 series stainless steel 
used with measuring THC or NMHC from compression-ignition engines, two-
stroke spark-ignition engines, and four-stroke spark-ignition engines at 
or below 19 kW. For all other engines and pollutants, these materials 
may be used for sample temperatures up to 202  deg.C.

[[Page 78]]



    Table 1 of Sec. 1065.170--Container Materials for Gaseous Batch
                                Sampling
------------------------------------------------------------------------
                                                Engine type
                                 ---------------------------------------
                                     Compression-
                                     ignition Two-
            Emissions                stroke spark-
                                    ignition Four-     All other engines
                                     stroke spark-
                                    ignition at or
                                      below 19 kW
------------------------------------------------------------------------
CO, CO2, O2, CH4, C2H6, C3H8,     Tedlar \TM\, Kynar  Tedlar \TM\, Kynar
 NO, NO2, N2O.                     \TM\, Teflon        \TM\, Teflon
                                   \TM\, or 300        \TM\, or 300
                                   series stainless    series stainless
                                   steel.              steel.
THC, NMHC.......................  Teflon \TM\ or 300  Tedlar \TM\, Kynar
                                   series stainless    \TM\, Teflon
                                   steel.              \TM\, or 300
                                                       series stainless
                                                       steel.
------------------------------------------------------------------------

    (c) PM sample media. Apply the following methods for sampling 
particulate emissions:
    (1) If you use filter-based sampling media to extract and store PM 
for measurement, your procedure must meet the following specifications:
    (i) If you expect that a filter's total surface concentration of PM 
will exceed 400 [micro] g, assuming a 38 mm diameter filter stain area, 
for a given test interval, you may use filter media with a minimum 
initial collection efficiency of 98%; otherwise you must use a filter 
media with a minimum initial collection efficiency of 99.7%. Collection 
efficiency must be measured as described in ASTM D2986 (incorporated by 
reference in Sec. 1065.1010), though you may rely on the sample-media 
manufacturer's measurements reflected in their product ratings to show 
that you meet this requirement.
    (ii) The filter must be circular, with an overall diameter of 46.50 
[0.6 mm and an exposed diameter of at least 38 mm. See the cassette 
specifications in paragraph (c)(1)(vii) of this section.
    (iii) We highly recommend that you use a pure PTFE filter material 
that does not have any flow-through support bonded to the back and has 
an overall thickness of 40 [20 [micro] m. An inert polymer ring may be 
bonded to the periphery of the filter material for support and for 
sealing between the filter cassette parts. We consider Polymethylpentene 
(PMP) and PTFE inert materials for a support ring, but other inert 
materials may be used. See the cassette specifications in paragraph 
(c)(1)(vii) of this section. We allow the use of PTFE-coated glass fiber 
filter material, as long as this filter media selection does not affect 
your ability to demonstrate compliance with the applicable standards, 
which we base on a pure PTFE filter material. Note that we will use pure 
PTFE filter material for compliance testing, and we may require you to 
use pure PTFE filter material for any compliance testing we require, 
such as for selective enforcement audits.
    (iv) You may request to use other filter materials or sizes under 
the provisions of Sec. 1065.10.
    (v) To minimize turbulent deposition and to deposit PM evenly on a 
filter, use a filter holder with a 12.5 deg. (from center) divergent 
cone angle to transition from the transfer-line inside diameter to the 
exposed diameter of the filter face. Use 300 series stainless steel for 
this transition.
    (vi) Maintain a filter face velocity near 100 cm/s with less than 5% 
of the recorded flow values exceeding 100 cm/s, unless you expect the 
net PM mass on the filter to exceed 400 [micro] g, assuming a 38 mm 
diameter filter stain area. Measure face velocity as the volumetric flow 
rate of the sample at the pressure upstream of the filter and 
temperature of the filter face as measured in Sec. 1065.140(e), divided 
by the filter's exposed area. You may use the exhaust stack or CVS 
tunnel pressure for the upstream pressure if the pressure drop through 
the PM sampler up to the filter is less than 2 kPa.
    (vii) Use a clean cassette designed to the specifications of Figure 
1 of Sec. 1065.170. In auto changer configurations, you may use 
cassettes of similar design. Cassettes must be made of one of the 
following materials: Delrin \TM\, 300 series stainless steel, 
polycarbonate, acrylonitrile-butadiene-styrene (ABS) resin, or 
conductive polypropylene. We recommend that you keep filter cassettes 
clean by periodically washing or wiping them with a compatible solvent 
applied using a

[[Page 79]]

lint-free cloth. Depending upon your cassette material, ethanol 
(C2H5OH) might be an acceptable solvent. Your 
cleaning frequency will depend on your engine's PM and HC emissions.
    (viii) If you keep the cassette in the filter holder after sampling, 
prevent flow through the filter until either the holder or cassette is 
removed from the PM sampler. If you remove the cassettes from filter 
holders after sampling, transfer the cassette to an individual container 
that is covered or sealed to prevent communication of semi-volatile 
matter from one filter to another. If you remove the filter holder, cap 
the inlet and outlet. Keep them covered or sealed until they return to 
the stabilization or weighing environments.
    (ix) The filters should not be handled outside of the PM 
stabilization and weighing environments and should be loaded into 
cassettes, filter holders, or auto changer apparatus before removal from 
these environments.
    (2) You may use other PM sample media that we approve under Sec. 
1065.10, including non-filtering techniques. For example, you might 
deposit PM on an inert substrate that collects PM using electrostatic, 
thermophoresis, inertia, diffusion, or some other deposition mechanism, 
as approved.
[GRAPHIC] [TIFF OMITTED] TR25OC16.158


[70 FR 40516, July 13, 2005, as amended at 73 FR 37298, June 30, 2008; 
73 FR 59321, Oct. 8, 2008; 76 FR 57440, Sept. 15, 2011;79 FR 23757, Apr. 
28, 2014; 81 FR 74162, Oct. 25, 2016]



Sec. 1065.190  PM-stabilization and weighing environments for 
gravimetric analysis.

    (a) This section describes the two environments required to 
stabilize and weigh PM for gravimetric analysis: the PM stabilization 
environment, where filters are stored before weighing; and

[[Page 80]]

the weighing environment, where the balance is located. The two 
environments may share a common space. These volumes may be one or more 
rooms, or they may be much smaller, such as a glove box or an automated 
weighing system consisting of one or more countertop-sized environments.
    (b) We recommend that you keep both the stabilization and the 
weighing environments free of ambient contaminants, such as dust, 
aerosols, or semi-volatile material that could contaminate PM samples. 
We recommend that these environments conform with an ``as-built'' Class 
Six clean room specification according to ISO 14644-1 (incorporated by 
reference in Sec. 1065.1010); however, we also recommend that you 
deviate from ISO 14644-1 as necessary to minimize air motion that might 
affect weighing. We recommend maximum air-supply and air-return 
velocities of 0.05 m/s in the weighing environment.
    (c) Verify the cleanliness of the PM-stabilization environment using 
reference filters, as described in Sec. 1065.390(d).
    (d) Maintain the following ambient conditions within the two 
environments during all stabilization and weighing:
    (1) Ambient temperature and tolerances. Maintain the weighing 
environment at a tolerance of (22 [1)  deg.C. If the two environments 
share a common space, maintain both environments at a tolerance of (22 
[1)  deg.C. If they are separate, maintain the stabilization environment 
at a tolerance of (22 [3)  deg.C.
    (2) Dewpoint. Maintain a dewpoint of 9.5  deg.C in both 
environments. This dewpoint will control the amount of water associated 
with sulfuric acid (H2SO4) PM, such that 1.2216 
grams of water will be associated with each gram of 
H2SO4.
    (3) Dewpoint tolerances. If the expected fraction of sulfuric acid 
in PM is unknown, we recommend controlling dewpoint at within [1  deg.C 
tolerance. This would limit any dewpoint-related change in PM to less 
than [2%, even for PM that is 50% sulfuric acid. If you know your 
expected fraction of sulfuric acid in PM, we recommend that you select 
an appropriate dewpoint tolerance for showing compliance with emission 
standards using the following table as a guide:

       Table 1 of Sec. 1065.190--Dewpoint Tolerance as a Function of % PM Change and % Sulfuric Acid PM
----------------------------------------------------------------------------------------------------------------
 Expected sulfuric acid fraction of
                 PM                     [0.5% PM mass change       [1% PM mass change       [2% PM mass change
----------------------------------------------------------------------------------------------------------------
5%..................................  [3 C....................  [6 C...................  [12 C
50%.................................  [0.3 C..................  [0.6 C.................  [1.2 C
100%................................  [0.15 C.................  [0.3 C.................  [0.6 C
----------------------------------------------------------------------------------------------------------------

    (e) Verify the following ambient conditions using measurement 
instruments that meet the specifications in subpart C of this part:
    (1) Continuously measure dewpoint and ambient temperature. Use these 
values to determine if the stabilization and weighing environments have 
remained within the tolerances specified in paragraph (d) of this 
section for at least 60 min. before weighing sample media (e.g., 
filters). We recommend that you use an interlock that automatically 
prevents the balance from reporting values if either of the environments 
have not been within the applicable tolerances for the past 60 min.
    (2) Continuously measure atmospheric pressure within the weighing 
environment. An acceptable alternative is to use a barometer that 
measures atmospheric pressure outside the weighing environment, as long 
as you can ensure that atmospheric pressure at the balance is always 
within [100 Pa of that outside environment during weighing operations. 
Record atmospheric pressure as you weigh filters, and use these pressure 
values to perform the buoyancy correction in Sec. 1065.690.
    (f) We recommend that you install a balance as follows:

[[Page 81]]

    (1) Install the balance on a vibration-isolation platform to isolate 
it from external noise and vibration.
    (2) Shield the balance from convective airflow with a static-
dissipating draft shield that is electrically grounded.
    (3) Follow the balance manufacturer's specifications for all 
preventive maintenance.
    (4) Operate the balance manually or as part of an automated weighing 
system.
    (g) Minimize static electric charge in the balance environment, as 
follows:
    (1) Electrically ground the balance.
    (2) Use 300 series stainless steel tweezers if PM sample media 
(e.g., filters) must be handled manually.
    (3) Ground tweezers with a grounding strap, or provide a grounding 
strap for the operator such that the grounding strap shares a common 
ground with the balance. Make sure grounding straps have an appropriate 
resistor to protect operators from accidental shock.
    (4) Provide a static-electricity neutralizer that is electrically 
grounded in common with the balance to remove static charge from PM 
sample media (e.g., filters), as follows:
    (i) You may use radioactive neutralizers such as a Polonium 
(210Po) source. Replace radioactive sources at the intervals 
recommended by the neutralizer manufacturer.
    (ii) You may use other neutralizers, such as corona-discharge 
ionizers. If you use a corona-discharge ionizer, we recommend that you 
monitor it for neutral net charge according to the ionizer 
manufacturer's recommendations.
    (5) We recommend that you use a device to monitor the static charge 
of PM sample media (e.g., filter) surface.
    (6) We recommend that you neutralize PM sample media (e.g., filters) 
to within [2.0 V of neutral. Measure static voltages as follows:
    (i) Measure static voltage of PM sample media (e.g., filters) 
according to the electrostatic voltmeter manufacturer's instructions.
    (ii) Measure static voltage of PM sample media (e.g., filters) while 
the media is at least 15 cm away from any grounded surfaces to avoid 
mirror image charge interference.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37299, June 30, 2008; 
73 FR 59323, Oct. 8, 2008; 76 FR 57440, Sept. 15, 2011]



Sec. 1065.195  PM-stabilization environment for in-situ analyzers.

    (a) This section describes the environment required to determine PM 
in-situ. For in-situ analyzers, such as an inertial balance, this is the 
environment within a PM sampling system that surrounds the PM sample 
media (e.g., filters). This is typically a very small volume.
    (b) Maintain the environment free of ambient contaminants, such as 
dust, aerosols, or semi-volatile material that could contaminate PM 
samples. Filter all air used for stabilization with HEPA filters. Ensure 
that HEPA filters are installed properly so that background PM does not 
leak past the HEPA filters.
    (c) Maintain the following thermodynamic conditions within the 
environment before measuring PM:
    (1) Ambient temperature. Select a nominal ambient temperature, Tamb, 
between (42 and 52)  deg.C. Maintain the ambient temperature within [1.0 
 deg.C of the selected nominal value.
    (2) Dewpoint. Select a dewpoint, Tdew, that corresponds to Tamb such 
that Tdew = (0.95Tamb-11.40)  deg.C. The resulting dewpoint will control 
the amount of water associated with sulfuric acid 
(H2SO4) PM, such that 1.1368 grams of water will 
be associated with each gram of H2SO4. For 
example, if you select a nominal ambient temperature of 47  deg.C, set a 
dewpoint of 33.3  deg.C.
    (3) Dewpoint tolerance. If the expected fraction of sulfuric acid in 
PM is unknown, we recommend controlling dewpoint within [1.0  deg.C. 
This would limit any dewpoint-related change in PM to less than [2%, 
even for PM that is 50% sulfuric acid. If you know your expected 
fraction of sulfuric acid in PM, we recommend that you select an 
appropriate dewpoint tolerance for showing compliance with emission 
standards using Table 1 of Sec. 1065.190 as a guide:

[[Page 82]]

    (4) Absolute pressure. Use good engineering judgment to maintain a 
tolerance of absolute pressure if your PM measurement instrument 
requires it.
    (d) Continuously measure dewpoint, temperature, and pressure using 
measurement instruments that meet the PM-stabilization environment 
specifications in subpart C of this part. Use these values to determine 
if the in-situ stabilization environment is within the tolerances 
specified in paragraph (c) of this section. Do not use any PM quantities 
that are recorded when any of these parameters exceed the applicable 
tolerances.
    (e) If you use an inertial PM balance, we recommend that you install 
it as follows:
    (1) Isolate the balance from any external noise and vibration that 
is within a frequency range that could affect the balance.
    (2) Follow the balance manufacturer's specifications.
    (f) If static electricity affects an inertial balance, you may use a 
static neutralizer, as follows:
    (1) You may use a radioactive neutralizer such as a Polonium 
(\210\Po) source or a Krypton (\85\Kr) source. Replace radioactive 
sources at the intervals recommended by the neutralizer manufacturer.
    (2) You may use other neutralizers, such as a corona-discharge 
ionizer. If you use a corona-discharge ionizer, we recommend that you 
monitor it for neutral net charge according to the ionizer 
manufacturer's recommendations.

[70 FR 40516, July 13, 2005, as amended at 73 FR 32799, June 30, 2008]



                    Subpart C_Measurement Instruments



Sec. 1065.201  Overview and general provisions.

    (a) Scope. This subpart specifies measurement instruments and 
associated system requirements related to emission testing in a 
laboratory or similar environment and in the field. This includes 
laboratory instruments and portable emission measurement systems (PEMS) 
for measuring engine parameters, ambient conditions, flow-related 
parameters, and emission concentrations.
    (b) Instrument types. You may use any of the specified instruments 
as described in this subpart to perform emission tests. If you want to 
use one of these instruments in a way that is not specified in this 
subpart, or if you want to use a different instrument, you must first 
get us to approve your alternate procedure under Sec. 1065.10. Where we 
specify more than one instrument for a particular measurement, we may 
identify which instrument serves as the reference for comparing with an 
alternate procedure. You may generally use instruments with compensation 
algorithms that are functions of other gaseous measurements and the 
known or assumed fuel properties for the test fuel. The target value for 
any compensation algorithm is 0% (that is, no bias high and no bias 
low), regardless of the uncompensated signal's bias.
    (c) Measurement systems. Assemble a system of measurement 
instruments that allows you to show that your engines comply with the 
applicable emission standards, using good engineering judgment. When 
selecting instruments, consider how conditions such as vibration, 
temperature, pressure, humidity, viscosity, specific heat, and exhaust 
composition (including trace concentrations) may affect instrument 
compatibility and performance.
    (d) Redundant systems. For all measurement instruments described in 
this subpart, you may use data from multiple instruments to calculate 
test results for a single test. If you use redundant systems, use good 
engineering judgment to use multiple measured values in calculations or 
to disregard individual measurements. Note that you must keep your 
results from all measurements. This requirement applies whether or not 
you actually use the measurements in your calculations.
    (e) Range. You may use an instrument's response above 100% of its 
operating range if this does not affect your ability to show that your 
engines comply with the applicable emission standards. Note that we 
require additional testing and reporting if an analyzer responds above 
100% of its range. Auto-

[[Page 83]]

ranging analyzers do not require additional testing or reporting.
    (f) Related subparts for laboratory testing. Subpart D of this part 
describes how to evaluate the performance of the measurement instruments 
in this subpart. In general, if an instrument is specified in a specific 
section of this subpart, its calibration and verifications are typically 
specified in a similarly numbered section in subpart D of this part. For 
example, Sec. 1065.290 gives instrument specifications for PM balances 
and Sec. 1065.390 describes the corresponding calibrations and 
verifications. Note that some instruments also have other requirements 
in other sections of subpart D of this part. Subpart B of this part 
identifies specifications for other types of equipment, and subpart H of 
this part specifies engine fluids and analytical gases.
    (g) Field testing and testing with PEMS. Subpart J of this part 
describes how to use these and other measurement instruments for field 
testing and other PEMS testing.
    (h) Recommended practices. This subpart identifies a variety of 
recommended but not required practices for proper measurements. We 
believe in most cases it is necessary to follow these recommended 
practices for accurate and repeatable measurements. However, we do not 
specifically require you to follow these recommended practices to 
perform a valid test, as long as you meet the required calibrations and 
verifications of measurement systems specified in subpart D of this 
part. Similarly, we are not required to follow all recommended 
practices, as long as we meet the required calibrations and 
verifications. Our decision to follow or not follow a given 
recommendation when we perform a test does not depend on whether you 
followed it during your testing.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37299, June 30, 2008; 
75 FR 23033, Apr. 30, 2010; 79 FR 23758, Apr. 29, 2014]



Sec. 1065.202  Data updating, recording, and control.

    Your test system must be able to update data, record data and 
control systems related to operator demand, the dynamometer, sampling 
equipment, and measurement instruments. Set up the measurement and 
recording equipment to avoid aliasing by ensuring that the sampling 
frequency is at least double that of the signal you are measuring, 
consistent with good engineering judgment; this may require increasing 
the sampling rate or filtering the signal. Use data acquisition and 
control systems that can record at the specified minimum frequencies, as 
follows:

                   Table 1 of Sec. 1065.202--Data Recording and Control Minimum Frequencies
----------------------------------------------------------------------------------------------------------------
                                                              Minimum command and
 Applicable test protocol section       Measured values        control frequency    Minimum recording frequency
                                                                      \a\                     \b\ \c\
----------------------------------------------------------------------------------------------------------------
Sec. 1065.510..................  Speed and torque during   1 Hz................  1 mean value per step.
                                    an engine step-map.
Sec. 1065.510..................  Speed and torque during   5 Hz................  1 Hz means.
                                    an engine sweep-map.
Sec. 1065.514; Sec. 1065.530.  Transient duty cycle      5 Hz................  1 Hz means.
                                    reference and feedback
                                    speeds and torques.
Sec. 1065.514; Sec. 1065.530.  Steady-state and ramped-  1 Hz................  1 Hz.
                                    modal duty cycle
                                    reference and feedback
                                    speeds and torques.
Sec. 1065.520; Sec. 1065.530;  Continuous                ....................  1 Hz.
 Sec. 1065.550.                   concentrations of raw
                                    or dilute analyzers.
Sec. 1065.520; Sec. 1065.530   Batch concentrations of   ....................  1 mean value per test
 Sec. 1065.550.                   raw or dilute analyzers.                        interval.
Sec. 1065.530; Sec. 1065.545.  Diluted exhaust flow      ....................  1 Hz.
                                    rate from a CVS with a
                                    heat exchanger upstream
                                    of the flow measurement.
Sec. 1065.530; Sec. 1065.545.  Diluted exhaust flow      5 Hz................  1 Hz means.
                                    rate from a CVS without
                                    a heat exchanger
                                    upstream of the flow
                                    measurement.
Sec. 1065.530; Sec. 1065.545.  Intake-air or raw-        ....................  1 Hz means.
                                    exhaust flow rate.

[[Page 84]]

 
Sec. 1065.530; Sec. 1065.545.  Dilution air flow if      5 Hz................  1 Hz means.
                                    actively controlled
                                    (for example, a partial-
                                    flow PM sampling
                                    system) \d\.
Sec. 1065.530; Sec. 1065.545.  Sample flow from a CVS    1 Hz................  1 Hz.
                                    that has a heat
                                    exchanger.
Sec. 1065.530; Sec. 1065.545.  Sample flow from a CVS    5 Hz................  1 Hz means.
                                    that does not have a
                                    heat exchanger.
----------------------------------------------------------------------------------------------------------------
\a\ The specifications for minimum command and control frequency do not apply for CFVs that are not using active
  control.
\b\ 1 Hz means are data reported from the instrument at a higher frequency, but recorded as a series of 1 s mean
  values at a rate of 1 Hz.
\c\ For CFVs in a CVS, the minimum recording frequency is 1 Hz. The minimum recording frequency does not apply
  for CFVs used to control sampling from a CVS utilizing CFVs.
\d\ Dilution air flow specifications do not apply for CVS dilution air.


[79 FR 23759, Apr. 28, 2014, as amended at 81 FR 74162, Oct. 25, 2016]



Sec. 1065.205  Performance specifications for measurement instruments.

    Your test system as a whole must meet all the calibrations, 
verifications, and test-validation criteria specified outside this 
section for laboratory testing or field testing, as applicable. We 
recommend that your instruments meet the specifications in Table 1 of 
this section for all ranges you use for testing. We also recommend that 
you keep any documentation you receive from instrument manufacturers 
showing that your instruments meet the specifications in Table 1 of this 
section.

                             Table 1 of Sec. 1065.205--Recommended Performance Specifications for Measurement Instruments
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                        Complete system
                                   Measured quantity  rise time (t10	90)   Recording update
     Measurement instrument             symbol           and fall time         frequency         Accuracy \b\      Repeatability \b\       Noise \b\
                                                         (t90	10) \a\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Engine speed transducer.........  fn................  1 s...............  1 Hz means........  2% of pt. or 0.5%   1% of pt. or 0.25%  0.05% of max.
                                                                                               of max.             of max.
Engine torque transducer........  T.................  1 s...............  1 Hz means........  2% of pt. or 1% of  1% of pt. or 0.5%   0.05% of max.
                                                                                               max.                of max.
Electrical work (active-power     W.................  1 s...............  1 Hz means........  2% of pt. or 0.5%   1% of pt. or 0.25%  0.05% of max.
 meter).                                                                                       of max.             of max.
General pressure transducer (not  p.................  5 s...............  1 Hz..............  2% of pt. or 1% of  1% of pt. or 0.5%   0.1% of max.
 a part of another instrument).                                                                max.                of max.
Atmospheric pressure meter for    patmos............  50 s..............  5 times per hour..  50 Pa.............  25 Pa.............  5 Pa
 PM-stabilization and balance
 environments.
General purpose atmospheric       patmos............  50 s..............  5 times per hour..  250 Pa............  100Pa.............  50 Pa
 pressure meter.
Temperature sensor for PM-        T.................  50 s..............  0.1 Hz............  0.25 K............  0.1 K.............  0.1 K
 stabilization and balance
 environments.
Other temperature sensor (not a   T.................  10 s..............  0.5 Hz............  0.4% of pt. K or    0.2% of pt. K or    0.1% of max.
 part of another instrument).                                                                  0.2% of max K.      0.1% of max K.
Dewpoint sensor for intake air,   Tdew..............  50 s..............  0.1 Hz............  0.25 K............  0.1 K.............  0.02 K
 PM-stabilization and balance
 environments.

[[Page 85]]

 
Other dewpoint sensor...........  Tdew..............  50 s..............  0.1 Hz............  1 K...............  0.5 K.............  0.1 K
Fuel flow meter \c\ (Fuel         m.................  5 s...............  1 Hz..............  2% of pt. or 1.5%   1% of pt. or 0.75%  0.5% of max.
 totalizer).                                          (--)..............  (--)..............   of max.             of max.
Total diluted exhaust meter       n.................  1 s...............  1 Hz means........  2% of pt. or 1.5%   1% of pt. or 0.75%  1% of max.
 (CVS) \c\ (With heat exchanger                       (5 s).............  (1 Hz)............   of max.             of max.
 before meter).
Dilution air, inlet air,          n.................  1 s...............  1 Hz means of 5 Hz  2.5% of pt. or      1.25% of pt. or     1% of max.
 exhaust, and sample flow meters                                           samples.            1.5% of max.        0.75% of max.
 \c\.
Continuous gas analyzer.........  x.................  5 s...............  1 Hz..............  2% of pt. or 2% of  1% of pt. or 1% of  1% of max.
                                                                                               meas.               meas.
Batch gas analyzer..............  x.................  ..................  ..................  2% of pt. or 2% of  1% of pt. or 1% of  1% of max.
                                                                                               meas.               meas.
Gravimetric PM balance..........  mPM...............  ..................  ..................  See Sec. 0.5 [micro] g
                                                                                               1065.790.
Inertial PM balance.............  mPM...............  5 s...............  1 Hz..............  2% of pt. or 2% of  1% of pt. or 1% of  0.2% of max
                                                                                               meas.               meas.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ The performance specifications identified in the table apply separately for rise time and fall time.
\b\ Accuracy, repeatability, and noise are all determined with the same collected data, as described in Sec. 1065.305, and based on absolute values.
  ``pt.'' refers to the overall flow-weighted mean value expected at the standard; ``max'' refers to the peak value expected at the standard over any
  test interval, not the maximum of the instrument's range; ``meas'' refers to the actual flow-weighted mean measured over any test interval.
\c\ The procedure for accuracy, repeatability and noise measurement described in Sec. 1065.305 may be modified for flow meters to allow noise to be
  measured at the lowest calibrated value instead of zero flow rate.


[79 FR 23759, Apr. 28, 2014]

         Measurement of Engine Parameters and Ambient Conditions



Sec. 1065.210  Work input and output sensors.

    (a) Application. Use instruments as specified in this section to 
measure work inputs and outputs during engine operation. We recommend 
that you use sensors, transducers, and meters that meet the 
specifications in Table 1 of Sec. 1065.205. Note that your overall 
systems for measuring work inputs and outputs must meet the linearity 
verifications in Sec. 1065.307. We recommend that you measure work 
inputs and outputs where they cross the system boundary as shown in 
Figure 1 of Sec. 1065.210. The system boundary is different for air-
cooled engines than for liquid-cooled engines. If you choose to measure 
work before or after a work conversion, relative to the system boundary, 
use good engineering judgment to estimate any work-conversion losses in 
a way that avoids overestimation of total work. For example, if it is 
impractical to instrument the shaft of an exhaust turbine generating 
electrical work, you may decide to measure its converted electrical 
work. As another example, you may decide to measure the tractive (i.e., 
electrical output) power of a locomotive, rather than the brake power of 
the locomotive engine. In these cases, divide the electrical work by 
accurate values of electrical generator efficiency (h<1), or assume an 
efficiency of 1 (h = 1), which would over-estimate brake-specific 
emissions. For the example of using locomotive tractive power with a 
generator efficiency of 1 (h = 1), this means using the tractive power 
as the brake power in emission calculations. Do not underestimate any 
work conversion efficiencies for any components outside the system 
boundary that do not return work into the system boundary. And do not 
overestimate any work conversion efficiencies for components outside the 
system boundary that do return work into the system boundary. In all 
cases, ensure that you are able to accurately demonstrate compliance 
with the applicable standards.

[[Page 86]]

[GRAPHIC] [TIFF OMITTED] TR13JY05.015

    (b) Shaft work. Use speed and torque transducer outputs to calculate 
total work according to Sec. 1065.650.
    (1) Speed. Use a magnetic or optical shaft-position detector with a 
resolution of at least 60 counts per revolution, in combination with a 
frequency

[[Page 87]]

counter that rejects common-mode noise.
    (2) Torque. You may use a variety of methods to determine engine 
torque. As needed, and based on good engineering judgment, compensate 
for torque induced by the inertia of accelerating and decelerating 
components connected to the flywheel, such as the drive shaft and 
dynamometer rotor. Use any of the following methods to determine engine 
torque:
    (i) Measure torque by mounting a strain gage or similar instrument 
in-line between the engine and dynamometer.
    (ii) Measure torque by mounting a strain gage or similar instrument 
on a lever arm connected to the dynamometer housing.
    (iii) Calculate torque from internal dynamometer signals, such as 
armature current, as long as you calibrate this measurement as described 
in Sec. 1065.310.
    (c) Electrical work. Use a watt-hour meter output to calculate total 
work according to Sec. 1065.650. Use a watt-hour meter that outputs 
active power. Watt-hour meters typically combine a Wheatstone bridge 
voltmeter and a Hall-effect clamp-on ammeter into a single 
microprocessor-based instrument that analyzes and outputs several 
parameters, such as alternating or direct current voltage, current, 
power factor, apparent power, reactive power, and active power.
    (d) Pump, compressor or turbine work. Use pressure transducer and 
flow-meter outputs to calculate total work according to Sec. 1065.650. 
For flow meters, see Sec. Sec. 1065.220 through 1065.248.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 
79 FR 23760, Apr. 28, 2014]



Sec. 1065.215  Pressure transducers, temperature sensors, and dewpoint
sensors.

    (a) Application. Use instruments as specified in this section to 
measure pressure, temperature, and dewpoint.
    (b) Component requirements. We recommend that you use pressure 
transducers, temperature sensors, and dewpoint sensors that meet the 
specifications in Table 1 of Sec. 1065.205. Note that your overall 
systems for measuring pressure, temperature, and dewpoint must meet the 
calibration and verifications in Sec. 1065.315.
    (c) Temperature. For PM-balance environments or other precision 
temperature measurements over a narrow temperature range, we recommend 
thermistors. For other applications we recommend thermocouples that are 
not grounded to the thermocouple sheath. You may use other temperature 
sensors, such as resistive temperature detectors (RTDs).
    (d) Pressure. Pressure transducers must be located in a temperature-
controlled environment, or they must compensate for temperature changes 
over their expected operating range. Transducer materials must be 
compatible with the fluid being measured. For atmospheric pressure or 
other precision pressure measurements, we recommend either capacitance-
type, quartz crystal, or laser-interferometer transducers. For other 
applications, we recommend either strain gage or capacitance-type 
pressure transducers. You may use other pressure-measurement 
instruments, such as manometers, where appropriate.
    (e) Dewpoint. For PM-stabilization environments, we recommend 
chilled-surface hygrometers, which include chilled mirror detectors and 
chilled surface acoustic wave (SAW) detectors. For other applications, 
we recommend thin-film capacitance sensors. You may use other dewpoint 
sensors, such as a wet-bulb/dry-bulb psychrometer, where appropriate.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008]

                        Flow-Related Measurements



Sec. 1065.220  Fuel flow meter.

    (a) Application. You may use fuel flow in combination with a 
chemical balance of fuel, inlet air, and raw exhaust to calculate raw 
exhaust flow as described in Sec. 1065.655(f), as follows:
    (1) Use the actual value of calculated raw exhaust flow rate in the 
following cases:
    (i) For multiplying raw exhaust flow rate with continuously sampled 
concentrations.

[[Page 88]]

    (ii) For multiplying total raw exhaust flow with batch-sampled 
concentrations.
    (iii) For calculating the dilution air flow for background 
correction as described in Sec. 1065.667.
    (2) In the following cases, you may use a fuel flow meter signal 
that does not give the actual value of raw exhaust, as long as it is 
linearly proportional to the exhaust molar flow rate's actual calculated 
value:
    (i) For feedback control of a proportional sampling system, such as 
a partial-flow dilution system.
    (ii) For multiplying with continuously sampled gas concentrations, 
if the same signal is used in a chemical-balance calculation to 
determine work from brake-specific fuel consumption and fuel consumed.
    (b) Component requirements. We recommend that you use a fuel flow 
meter that meets the specifications in Table 1 of Sec. 1065.205. We 
recommend a fuel flow meter that measures mass directly, such as one 
that relies on gravimetric or inertial measurement principles. This may 
involve using a meter with one or more scales for weighing fuel or using 
a Coriolis meter. Note that your overall system for measuring fuel flow 
must meet the linearity verification in Sec. 1065.307 and the 
calibration and verifications in Sec. 1065.320.
    (c) Recirculating fuel. In any fuel-flow measurement, account for 
any fuel that bypasses the engine or returns from the engine to the fuel 
storage tank.
    (d) Flow conditioning. For any type of fuel flow meter, condition 
the flow as needed to prevent wakes, eddies, circulating flows, or flow 
pulsations from affecting the accuracy or repeatability of the meter. 
You may accomplish this by using a sufficient length of straight tubing 
(such as a length equal to at least 10 pipe diameters) or by using 
specially designed tubing bends, straightening fins, or pneumatic 
pulsation dampeners to establish a steady and predictable velocity 
profile upstream of the meter. Condition the flow as needed to prevent 
any gas bubbles in the fuel from affecting the fuel meter.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 
76 FR 57441, Sept. 15, 2011; 81 FR 74162, Oct. 25, 2016]



Sec. 1065.225  Intake-air flow meter.

    (a) Application. You may use an intake-air flow meter in combination 
with a chemical balance of fuel, inlet air, and exhaust to calculate raw 
exhaust flow as described in Sec. 1065.655(f) and (g), as follows:
    (1) Use the actual value of calculated raw exhaust in the following 
cases:
    (i) For multiplying raw exhaust flow rate with continuously sampled 
concentrations.
    (ii) For multiplying total raw exhaust flow with batch-sampled 
concentrations.
    (iii) For verifying minimum dilution ratio for PM batch sampling as 
described in Sec. 1065.546.
    (iv) For calculating the dilution air flow for background correction 
as described in Sec. 1065.667.
    (2) In the following cases, you may use an intake-air flow meter 
signal that does not give the actual value of raw exhaust, as long as it 
is linearly proportional to the exhaust flow rate's actual calculated 
value:
    (i) For feedback control of a proportional sampling system, such as 
a partial-flow dilution system.
    (ii) For multiplying with continuously sampled gas concentrations, 
if the same signal is used in a chemical-balance calculation to 
determine work from brake-specific fuel consumption and fuel consumed.
    (b) Component requirements. We recommend that you use an intake-air 
flow meter that meets the specifications in Table 1 of Sec. 1065.205. 
This may include a laminar flow element, an ultrasonic flow meter, a 
subsonic venturi, a thermal-mass meter, an averaging Pitot tube, or a 
hot-wire anemometer. Note that your overall system for measuring intake-
air flow must meet the linearity verification in Sec. 1065.307 and the 
calibration in Sec. 1065.325.
    (c) Flow conditioning. For any type of intake-air flow meter, 
condition the

[[Page 89]]

flow as needed to prevent wakes, eddies, circulating flows, or flow 
pulsations from affecting the accuracy or repeatability of the meter. 
You may accomplish this by using a sufficient length of straight tubing 
(such as a length equal to at least 10 pipe diameters) or by using 
specially designed tubing bends, orifice plates or straightening fins to 
establish a predictable velocity profile upstream of the meter.

[70 FR 40516, July 13, 2005, as amended at 76 FR 57442, Sept. 15, 
2011;79 FR 23760, Apr. 28, 2014; 81 FR 74163, Oct. 25, 2016]



Sec. 1065.230  Raw exhaust flow meter.

    (a) Application. You may use measured raw exhaust flow, as follows:
    (1) Use the actual value of calculated raw exhaust in the following 
cases:
    (i) Multiply raw exhaust flow rate with continuously sampled 
concentrations.
    (ii) Multiply total raw exhaust with batch sampled concentrations.
    (2) In the following cases, you may use a raw exhaust flow meter 
signal that does not give the actual value of raw exhaust, as long as it 
is linearly proportional to the exhaust flow rate's actual calculated 
value:
    (i) For feedback control of a proportional sampling system, such as 
a partial-flow dilution system.
    (ii) For multiplying with continuously sampled gas concentrations, 
if the same signal is used in a chemical-balance calculation to 
determine work from brake-specific fuel consumption and fuel consumed.
    (b) Component requirements. We recommend that you use a raw-exhaust 
flow meter that meets the specifications in Table 1 of Sec. 1065.205. 
This may involve using an ultrasonic flow meter, a subsonic venturi, an 
averaging Pitot tube, a hot-wire anemometer, or other measurement 
principle. This would generally not involve a laminar flow element or a 
thermal-mass meter. Note that your overall system for measuring raw 
exhaust flow must meet the linearity verification in Sec. 1065.307 and 
the calibration and verifications in Sec. 1065.330. Any raw-exhaust 
meter must be designed to appropriately compensate for changes in the 
raw exhaust's thermodynamic, fluid, and compositional states.
    (c) Flow conditioning. For any type of raw exhaust flow meter, 
condition the flow as needed to prevent wakes, eddies, circulating 
flows, or flow pulsations from affecting the accuracy or repeatability 
of the meter. You may accomplish this by using a sufficient length of 
straight tubing (such as a length equal to at least 10 pipe diameters) 
or by using specially designed tubing bends, orifice plates or 
straightening fins to establish a predictable velocity profile upstream 
of the meter.
    (d) Exhaust cooling. You may cool raw exhaust upstream of a raw-
exhaust flow meter, as long as you observe all the following provisions:
    (1) Do not sample PM downstream of the cooling.
    (2) If cooling causes exhaust temperatures above 202  deg.C to 
decrease to below 180  deg.C, do not sample NMHC downstream of the 
cooling for compression-ignition engines, two-stroke spark-ignition 
engines, or four-stroke spark-ignition engines at or below 19 kW.
    (3) The cooling must not cause aqueous condensation.

[70 FR 40516, July 13, 2005, as amended at 79 FR 23761, Apr. 28, 2014]



Sec. 1065.240  Dilution air and diluted exhaust flow meters.

    (a) Application. Use a diluted exhaust flow meter to determine 
instantaneous diluted exhaust flow rates or total diluted exhaust flow 
over a test interval. You may use the difference between a diluted 
exhaust flow meter and a dilution air meter to calculate raw exhaust 
flow rates or total raw exhaust flow over a test interval.
    (b) Component requirements. We recommend that you use a diluted 
exhaust flow meter that meets the specifications in Table 1 of Sec. 
1065.205. Note that your overall system for measuring diluted exhaust 
flow must meet the linearity verification in Sec. 1065.307 and the 
calibration and verifications in Sec. 1065.340 and Sec. 1065.341. You 
may use the following meters:
    (1) For constant-volume sampling (CVS) of the total flow of diluted 
exhaust, you may use a critical-flow venturi (CFV) or multiple critical-
flow venturis arranged in parallel, a positive-displacement pump (PDP), 
a subsonic venturi (SSV), or an ultrasonic

[[Page 90]]

flow meter (UFM). Combined with an upstream heat exchanger, either a CFV 
or a PDP will also function as a passive flow controller in a CVS 
system. However, you may also combine any flow meter with any active 
flow control system to maintain proportional sampling of exhaust 
constituents. You may control the total flow of diluted exhaust, or one 
or more sample flows, or a combination of these flow controls to 
maintain proportional sampling.
    (2) For any other dilution system, you may use a laminar flow 
element, an ultrasonic flow meter, a subsonic venturi, a critical-flow 
venturi or multiple critical-flow venturis arranged in parallel, a 
positive-displacement meter, a thermal-mass meter, an averaging Pitot 
tube, or a hot-wire anemometer.
    (c) Flow conditioning. For any type of diluted exhaust flow meter, 
condition the flow as needed to prevent wakes, eddies, circulating 
flows, or flow pulsations from affecting the accuracy or repeatability 
of the meter. For some meters, you may accomplish this by using a 
sufficient length of straight tubing (such as a length equal to at least 
10 pipe diameters) or by using specially designed tubing bends, orifice 
plates or straightening fins to establish a predictable velocity profile 
upstream of the meter.
    (d) Exhaust cooling. You may cool diluted exhaust upstream of a 
dilute-exhaust flow meter, as long as you observe all the following 
provisions:
    (1) Do not sample PM downstream of the cooling.
    (2) If cooling causes exhaust temperatures above 202  deg.C to 
decrease to below 180  deg.C, do not sample NMHC downstream of the 
cooling for compression-ignition engines, two-stroke spark-ignition 
engines, or four-stroke spark-ignition engines at or below 19 kW.
    (3) The cooling must not cause aqueous condensation as described in 
Sec. 1065.140(c)(6).

[70 FR 40516, July 13, 2005, as amended at 75 FR 23035, Apr. 30, 2010; 
79 FR 23761, Apr. 28, 2014]



Sec. 1065.245  Sample flow meter for batch sampling.

    (a) Application. Use a sample flow meter to determine sample flow 
rates or total flow sampled into a batch sampling system over a test 
interval. You may use the difference between a diluted exhaust sample 
flow meter and a dilution air meter to calculate raw exhaust flow rates 
or total raw exhaust flow over a test interval.
    (b) Component requirements. We recommend that you use a sample flow 
meter that meets the specifications in Table 1 of Sec. 1065.205. This 
may involve a laminar flow element, an ultrasonic flow meter, a subsonic 
venturi, a critical-flow venturi or multiple critical-flow venturis 
arranged in parallel, a positive-displacement meter, a thermal-mass 
meter, an averaging Pitot tube, or a hot-wire anemometer. Note that your 
overall system for measuring sample flow must meet the linearity 
verification in Sec. 1065.307. For the special case where CFVs are used 
for both the diluted exhaust and sample-flow measurements and their 
upstream pressures and temperatures remain similar during testing, you 
do not have to quantify the flow rate of the sample-flow CFV. In this 
special case, the sample-flow CFV inherently flow-weights the batch 
sample relative to the diluted exhaust CFV.
    (c) Flow conditioning. For any type of sample flow meter, condition 
the flow as needed to prevent wakes, eddies, circulating flows, or flow 
pulsations from affecting the accuracy or repeatability of the meter. 
For some meters, you may accomplish this by using a sufficient length of 
straight tubing (such as a length equal to at least 10 pipe diameters) 
or by using specially designed tubing bends, orifice plates or 
straightening fins to establish a predictable velocity profile upstream 
of the meter.



Sec. 1065.247  Diesel exhaust fluid flow rate.

    (a) Application. Determine diesel exhaust fluid flow rate over a 
test interval for batch or continuous emission sampling using one of the 
three methods described in this section.
    (b) ECM. Use the ECM signal directly to determine diesel exhaust 
fluid flow rate. You may combine this with a gravimetric scale if that 
improves measurement quality. Prior to testing, you may characterize the 
ECM signal using a laboratory measurement and

[[Page 91]]

adjust the ECM signal, consistent with good engineering judgment.
    (c) Flow meter. Measure diesel exhaust fluid flow rate with a flow 
meter. We recommend that the flow meter that meets the specifications in 
Table 1 of Sec. 1065.205. Note that your overall system for measuring 
diesel exhaust fluid flow must meet the linearity verification in Sec. 
1065.307. Measure using the following procedure:
    (1) Condition the flow of diesel exhaust fluid as needed to prevent 
wakes, eddies, circulating flows, or flow pulsations from affecting the 
accuracy or repeatability of the meter. You may accomplish this by using 
a sufficient length of straight tubing (such as a length equal to at 
least 10 pipe diameters) or by using specially designed tubing bends, 
straightening fins, or pneumatic pulsation dampeners to establish a 
steady and predictable velocity profile upstream of the meter. Condition 
the flow as needed to prevent any gas bubbles in the fluid from 
affecting the flow meter.
    (2) Account for any fluid that bypasses the engine or returns from 
the engine to the fluid storage tank.
    (d) Gravimetric scale. Use a gravimetric scale to determine the mass 
of diesel exhaust fluid the engine uses over a discrete-mode test 
interval and divide by the time of the test interval.

[81 FR 74163, Oct. 25, 2016]



Sec. 1065.248  Gas divider.

    (a) Application. You may use a gas divider to blend calibration 
gases.
    (b) Component requirements. Use a gas divider that blends gases to 
the specifications of Sec. 1065.750 and to the flow-weighted 
concentrations expected during testing. You may use critical-flow gas 
dividers, capillary-tube gas dividers, or thermal-mass-meter gas 
dividers. Note that your overall gas-divider system must meet the 
linearity verification in Sec. 1065.307.

                   CO and CO2 Measurements



Sec. 1065.250  Nondispersive infrared analyzer.

    (a) Application. Use a nondispersive infrared (NDIR) analyzer to 
measure CO and CO2 concentrations in raw or diluted exhaust 
for either batch or continuous sampling.
    (b) Component requirements. We recommend that you use an NDIR 
analyzer that meets the specifications in Table 1 of Sec. 1065.205. 
Note that your NDIR-based system must meet the calibration and 
verifications in Sec. Sec. 1065.350 and 1065.355 and it must also meet 
the linearity verification in Sec. 1065.307.

[76 FR 57442, Sept. 15, 2011, as amended at 79 FR 23761, Apr. 28, 2014]

                        Hydrocarbon Measurements



Sec. 1065.260  Flame-ionization detector.

    (a) Application. Use a flame-ionization detector (FID) analyzer to 
measure hydrocarbon concentrations in raw or diluted exhaust for either 
batch or continuous sampling. Determine hydrocarbon concentrations on a 
carbon number basis of one, C1. For measuring THC or THCE you 
must use a FID analyzer. For measuring CH4 you must meet the 
requirements of paragraph (f) of this section. See subpart I of this 
part for special provisions that apply to measuring hydrocarbons when 
testing with oxygenated fuels.
    (b) Component requirements. We recommend that you use a FID analyzer 
that meets the specifications in Table 1 of Sec. 1065.205. Note that 
your FID-based system for measuring THC, THCE, or CH4 must 
meet all the verifications for hydrocarbon measurement in subpart D of 
this part, and it must also meet the linearity verification in Sec. 
1065.307.
    (c) Heated FID analyzers. For measuring THC or THCE from 
compression-ignition engines, two-stroke spark-ignition engines, and 
four-stroke spark-ignition engines at or below 19 kW, you must use 
heated FID analyzers that maintain all surfaces that are exposed to 
emissions at a temperature of (191 [11)  deg.C.
    (d) FID fuel and burner air. Use FID fuel and burner air that meet 
the specifications of Sec. 1065.750. Do not allow the FID fuel and 
burner air to mix before entering the FID analyzer to ensure that the 
FID analyzer operates with a diffusion flame and not a premixed flame.
    (e) NMHC and NMOG. For demonstrating compliance with NMHC

[[Page 92]]

standards, you may either measure THC or determine NMHC mass as 
described in Sec. 1065.660(b)(1), or you may measure THC and 
CH4 and determine NMHC as described in Sec. 1065.660(b)(2) 
or (3). For gaseous-fueled engines, you may also use the additive method 
in Sec. 1065.660(b)(4). See 40 CFR 1066.635 for methods to demonstrate 
compliance with NMOG standards for vehicle testing.
    (f) NMNEHC. For demonstrating compliance with NMNEHC standards, you 
may either measure NMHC or determine NMNEHC mass as described in Sec. 
1065.660(c)(1), you may measure THC, CH4, and 
C2H6 and determine NMNEHC as described in Sec. 
1065.660(c)(2), or you may use the additive method in Sec. 
1065.660(c)(3).
    (g) CH4. For reporting CH4 or for demonstrating 
compliance with CH4 standards, you may use a FID analyzer 
with a nonmethane cutter as described in Sec. 1065.265 or you may use a 
GC-FID as described in Sec. 1065.267. Determine CH4 as 
described in Sec. 1065.660(d).

[76 FR 57442, Sept. 15, 2011, as amended at 79 FR 23761, Apr. 28, 2014; 
81 FR 74163, Oct. 25, 2016]



Sec. 1065.265  Nonmethane cutter.

    (a) Application. You may use a nonmethane cutter to measure 
CH4 with a FID analyzer. A nonmethane cutter oxidizes all 
nonmethane hydrocarbons to CO2 and H2O. You may 
use a nonmethane cutter for raw or diluted exhaust for batch or 
continuous sampling.
    (b) System performance. Determine nonmethane-cutter performance as 
described in Sec. 1065.365 and use the results to calculate 
CH4 or NMHC emissions in Sec. 1065.660.
    (c) Configuration. Configure the nonmethane cutter with a bypass 
line if it is needed for the verification described in Sec. 1065.365.
    (d) Optimization. You may optimize a nonmethane cutter to maximize 
the penetration of CH4 and the oxidation of all other 
hydrocarbons. You may humidify a sample and you may dilute a sample with 
purified air or oxygen (O2) upstream of the nonmethane cutter 
to optimize its performance. You must account for any sample 
humidification and dilution in emission calculations.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 
76 FR 57442, Sept. 15, 2011]



Sec. 1065.266  Fourier transform infrared analyzer.

    (a) Application. For engines that run only on natural gas, you may 
use a Fourier transform infrared (FTIR) analyzer to measure nonmethane 
hydrocarbon (NMHC) and nonmethane-nonethane hydrocarbon (NMNEHC) for 
continuous sampling. You may use an FTIR analyzer with any gaseous-
fueled engine, including dual-fuel engines, to measure CH4 
and C2H6, for either batch or continuous sampling 
(for subtraction from THC).
    (b) Component requirements. We recommend that you use an FTIR 
analyzer that meets the specifications in Table 1 of Sec. 1065.205. 
Note that your FTIR-based system must meet the linearity verification in 
Sec. 1065.307. Use appropriate analytical procedures for interpretation 
of infrared spectra. For example, EPA Test Method 320 (see https://
www3.epa.gov/ttn/emc/promgate/m-320.pdf) and ASTM D6348 (incorporated by 
reference in Sec. 1065.1010) are considered valid methods for spectral 
interpretation. You must use heated FTIR analyzers that maintain all 
surfaces that are exposed to emissions at a temperature of (110 to 202) 
deg.C.
    (c) Hydrocarbon species for NMHC and NMNEHC additive determination. 
To determine NMNEHC, measure ethene, ethyne, propane, propene, butane, 
formaldehyde, acetaldehyde, formic acid, and methanol. To determine 
NMHC, measure ethane in addition to those same hydrocarbon species. 
Determine NMHC and NMNEHC as described in Sec. 1065.660(b)(4) and Sec. 
1065.660(c)(3).
    (d) NMHC and NMNEHC CH4 and C2H6 
determination from subtraction of CH4 and 
C2H6 from THC. Determine CH4 as 
described in Sec. 1065.660(d)(2) and C2H6 as 
described Sec. 1065.660(e). Determine NMHC from subtraction of 
CH4 from THC as described in Sec. 1065.660(b)(3) and NMNEHC 
from subtraction of CH4 and C2H6 as 
described Sec. 1065.660(c)(2). Determine CH4 as described in 
Sec. 1065.660(d)(2) and C2H6 as described Sec. 
1065.660(e).

[[Page 93]]

    (e) Interference verification. Perform interference verification for 
FTIR analyzers using the procedures of Sec. 1065.366. Certain 
interference gases can interfere with FTIR analyzers by causing a 
response similar to the hydrocarbon species of interest. When running 
the interference verification for these analyzers, use interference 
gases as follows:
    (1) The interference gases for CH4 are CO2, 
H2O, and C2H6.
    (2) The interference gases for C2H6 are 
CO2, H2O, and CH4.
    (3) The interference gases for other measured hydrocarbon species 
are CO2, H2O, CH4, and 
C2H6.

[81 FR 74163, Oct. 25, 2016]



Sec. 1065.267  Gas chromatograph with a flame ionization detector.

    (a) Application. You may use a gas chromatograph with a flame 
ionization detector (GC-FID) to measure CH4 and 
C2H6 concentrations of diluted exhaust for batch 
sampling. While you may also use a nonmethane cutter to measure 
CH4, as described in Sec. 1065.265, use a reference 
procedure based on a gas chromatograph for comparison with any proposed 
alternate measurement procedure under Sec. 1065.10.
    (b) Component requirements. We recommend that you use a GC-FID that 
meets the specifications in Table 1 of Sec. 1065.205 and that the 
measurement be done according to SAE J1151 (incorporated by reference in 
Sec. 1065.1010). The GC-FID must meet the linearity verification in 
Sec. 1065.307.

[76 FR 57442, Sept. 15, 2011, as amended at 79 FR 23761, Apr. 28, 2014; 
81 FR 74163, Oct. 25, 2016]



Sec. 1065.269  Photoacoustic analyzer for ethanol and methanol.

    (a) Application. You may use a photoacoustic analyzer to measure 
ethanol and/or methanol concentrations in diluted exhaust for batch 
sampling.
    (b) Component requirements. We recommend that you use a 
photoacoustic analyzer that meets the specifications in Table 1 of Sec. 
1065.205. Note that your photoacoustic system must meet the verification 
in Sec. 1065.369 and it must also meet the linearity verification in 
Sec. 1065.307. Use an optical wheel configuration that gives analytical 
priority to measurement of the least stable components in the sample. 
Select a sample integration time of at least 5 seconds. Take into 
account sample chamber and sample line volumes when determining flush 
times for your instrument.

[79 FR 23761, Apr. 28, 2014]

             NOX and N2O Measurements



Sec. 1065.270  Chemiluminescent detector.

    (a) Application. You may use a chemiluminescent detector (CLD) to 
measure NOX concentration in raw or diluted exhaust for batch 
or continuous sampling. We generally accept a CLD for NOX 
measurement, even though it measures only NO and NO2, when 
coupled with an NO2-to-NO converter, since conventional 
engines and aftertreatment systems do not emit significant amounts of 
NOX species other than NO and NO2. Measure other 
NOX species if required by the standard-setting part. While 
you may also use other instruments to measure NOX, as 
described in Sec. 1065.272, use a reference procedure based on a 
chemiluminescent detector for comparison with any proposed alternate 
measurement procedure under Sec. 1065.10.
    (b) Component requirements. We recommend that you use a CLD that 
meets the specifications in Table 1 of Sec. 1065.205. Note that your 
CLD-based system must meet the quench verification in Sec. 1065.370 and 
it must also meet the linearity verification in Sec. 1065.307. You may 
use a heated or unheated CLD, and you may use a CLD that operates at 
atmospheric pressure or under a vacuum.
    (c) NO2-to-NO converter. Place upstream of the CLD an internal or 
external NO2-to-NO converter that meets the verification in 
Sec. 1065.378. Configure the converter with a bypass line if it is 
needed to facilitate this verification.
    (d) Humidity effects. You must maintain all CLD temperatures to 
prevent aqueous condensation. If you remove humidity from a sample 
upstream of a CLD, use one of the following configurations:
    (1) Connect a CLD downstream of any dryer or chiller that is 
downstream of an NO2-to-NO converter that meets the 
verification in Sec. 1065.378.

[[Page 94]]

    (2) Connect a CLD downstream of any dryer or thermal chiller that 
meets the verification in Sec. 1065.376.
    (e) Response time. You may use a heated CLD to improve CLD response 
time.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37300, June 30, 2008; 
76 FR 57442, Sept. 15, 2011; 79 FR 23761, Apr. 28, 2014]



Sec. 1065.272  Nondispersive ultraviolet analyzer.

    (a) Application. You may use a nondispersive ultraviolet (NDUV) 
analyzer to measure NOX concentration in raw or diluted 
exhaust for batch or continuous sampling. We generally accept an NDUV 
for NOX measurement, even though it measures only NO and 
NO2, since conventional engines and aftertreatment systems do 
not emit significant amounts of other NOX species. Measure 
other NOX species if required by the standard-setting part. 
Note that good engineering judgment may preclude you from using an NDUV 
analyzer if sampled exhaust from test engines contains oil (or other 
contaminants) in sufficiently high concentrations to interfere with 
proper operation.
    (b) Component requirements. We recommend that you use an NDUV 
analyzer that meets the specifications in Table 1 of Sec. 1065.205. 
Note that your NDUV-based system must meet the verifications in Sec. 
1065.372 and it must also meet the linearity verification in Sec. 
1065.307.
    (c) NO2-to-NO converter. If your NDUV analyzer measures only NO, 
place upstream of the NDUV analyzer an internal or external 
NO2-to-NO converter that meets the verification in Sec. 
1065.378. Configure the converter with a bypass to facilitate this 
verification.
    (d) Humidity effects. You must maintain NDUV temperature to prevent 
aqueous condensation, unless you use one of the following 
configurations:
    (1) Connect an NDUV downstream of any dryer or chiller that is 
downstream of an NO2-to-NO converter that meets the 
verification in Sec. 1065.378.
    (2) Connect an NDUV downstream of any dryer or thermal chiller that 
meets the verification in Sec. 1065.376.

[70 FR 40516, July 13, 2005, as amended at 73 FR 59323, Oct. 8, 2008; 76 
FR 57442, Sept. 15, 2011; 79 FR 23761, Apr. 28, 2014]



Sec. 1065.275  N[bdi2] O measurement devices.

    (a) General component requirements. We recommend that you use an 
analyzer that meets the specifications in Table 1 of Sec. 1065.205. 
Note that your system must meet the linearity verification in Sec. 
1065.307.
    (b) Instrument types. You may use any of the following analyzers to 
measure N2O:
    (1) Nondispersive infrared (NDIR) analyzer.
    (2) Fourier transform infrared (FTIR) analyzer. Use appropriate 
analytical procedures for interpretation of infrared spectra. For 
example, EPA Test Method 320 (see https://www3.epa.gov/ttn/emc/promgate/
m-320.pdf) and ASTM D6348 (incorporated by reference in Sec. 1065.1010) 
are considered valid methods for spectral interpretation.
    (3) Laser infrared analyzer. Examples of laser infrared analyzers 
are pulsed-mode high-resolution narrow band mid-infrared analyzers, and 
modulated continuous wave high-resolution narrow band mid-infrared 
analyzers.
    (4) Photoacoustic analyzer. Use an optical wheel configuration that 
gives analytical priority to measurement of the least stable components 
in the sample. Select a sample integration time of at least 5 seconds. 
Take into account sample chamber and sample line volumes when 
determining flush times for your instrument.
    (5) Gas chromatograph analyzer. You may use a gas chromatograph with 
an electron-capture detector (GC-ECD) to measure N2O 
concentrations of diluted exhaust for batch sampling.
    (i) You may use a packed or porous layer open tubular (PLOT) column 
phase of suitable polarity and length to achieve adequate resolution of 
the N2O peak for analysis. Examples of acceptable columns are 
a PLOT column consisting of bonded polystyrene-divinylbenzene or a 
Porapack Q packed column. Take the column temperature profile and 
carrier gas selection into consideration when setting up your

[[Page 95]]

method to achieve adequate N2O peak resolution.
    (ii) Use good engineering judgment to zero your instrument and 
correct for drift. You do not need to follow the specific procedures in 
Sec. Sec. 1065.530 and 1065.550(b) that would otherwise apply. For 
example, you may perform a span gas measurement before and after sample 
analysis without zeroing and use the average area counts of the pre-span 
and post-span measurements to generate a response factor (area counts/
span gas concentration), which you then multiply by the area counts from 
your sample to generate the sample concentration.
    (c) Interference verification. Perform interference verification for 
NDIR, FTIR, laser infrared analyzers, and photoacoustic analyzers using 
the procedures of Sec. 1065.375. Interference verification is not 
required for GC-ECD. Certain interference gases can positively interfere 
with NDIR, FTIR, and photoacoustic analyzers by causing a response 
similar to N2O. When running the interference verification 
for these analyzers, use interference gases as follows:
    (1) The interference gases for NDIR analyzers are CO, 
CO2, H2O, CH4, and SO2. Note 
that interference species, with the exception of H2O, are 
dependent on the N2O infrared absorption band chosen by the 
instrument manufacturer. For each analyzer determine the N2O 
infrared absorption band. For each N2O infrared absorption 
band, use good engineering judgment to determine which interference 
gases to use in the verification.
    (2) Use good engineering judgment to determine interference gases 
for FTIR, and laser infrared analyzers. Note that interference species, 
with the exception of H2O, are dependent on the 
N2O infrared absorption band chosen by the instrument 
manufacturer. For each analyzer determine the N2O infrared 
absorption band. For each N2O infrared absorption band, use 
good engineering judgment to determine interference gases to use in the 
verification.
    (3) The interference gases for photoacoustic analyzers are CO, 
CO2, and H2O.

[74 FR 56512, Oct. 30, 2009, as amended at 76 FR 57443, Sept. 15, 2011; 
78 FR 36398, June 17, 2013;79 FR 23761, Apr. 28, 2014; 81 FR 74163, Oct. 
25, 2016]

                       O2 Measurements



Sec. 1065.280  Paramagnetic and magnetopneumatic O[bdi2] detection
analyzers.

    (a) Application. You may use a paramagnetic detection (PMD) or 
magnetopneumatic detection (MPD) analyzer to measure O2 
concentration in raw or diluted exhaust for batch or continuous 
sampling. You may use O2 measurements with intake air or fuel 
flow measurements to calculate exhaust flow rate according to Sec. 
1065.650.
    (b) Component requirements. We recommend that you use a PMD or MPD 
analyzer that meets the specifications in Table 1 of Sec. 1065.205. 
Note that it must meet the linearity verification in Sec. 1065.307.

[73 FR 37300, June 30, 2008, as amended at 76 FR 57443, Sept. 15, 
2011;79 FR 23762, Apr. 28, 2014]

                     Air-to-Fuel Ratio Measurements



Sec. 1065.284  Zirconia (ZrO[bdi2] ) analyzer.

    (a) Application. You may use a zirconia (ZrO2) analyzer 
to measure air-to-fuel ratio in raw exhaust for continuous sampling. You 
may use O2 measurements with intake air or fuel flow 
measurements to calculate exhaust flow rate according to Sec. 1065.650.
    (b) Component requirements. We recommend that you use a 
ZrO2 analyzer that meets the specifications in Table 1 of 
Sec. 1065.205. Note that your ZrO2-based system must meet 
the linearity verification in Sec. 1065.307.

[70 FR 40516, July 13, 2005, as amended at 76 FR 57443, Sept. 15, 2011; 
79 FR 23762, Apr. 28, 2014]

                             PM Measurements



Sec. 1065.290  PM gravimetric balance.

    (a) Application. Use a balance to weigh net PM on a sample medium 
for laboratory testing.

[[Page 96]]

    (b) Component requirements. We recommend that you use a balance that 
meets the specifications in Table 1 of Sec. 1065.205. Note that your 
balance-based system must meet the linearity verification in Sec. 
1065.307. If the balance uses internal calibration weights for routine 
spanning and the weights do not meet the specifications in Sec. 
1065.790, the weights must be verified independently with external 
calibration weights meeting the requirements of Sec. 1065.790. While 
you may also use an inertial balance to measure PM, as described in 
Sec. 1065.295, use a reference procedure based on a gravimetric balance 
for comparison with any proposed alternate measurement procedure under 
Sec. 1065.10.
    (c) Pan design. We recommend that you use a balance pan designed to 
minimize corner loading of the balance, as follows:
    (1) Use a pan that centers the PM sample media (such as a filter) on 
the weighing pan. For example, use a pan in the shape of a cross that 
has upswept tips that center the PM sample media on the pan.
    (2) Use a pan that positions the PM sample as low as possible.
    (d) Balance configuration. Configure the balance for optimum 
settling time and stability at your location.

[73 FR 37300, June 30, 2008, as amended at 75 FR 68462, Nov. 8, 2010]



Sec. 1065.295  PM inertial balance for field-testing analysis.

    (a) Application. You may use an inertial balance to quantify net PM 
on a sample medium for field testing.
    (b) Component requirements. We recommend that you use a balance that 
meets the specifications in Table 1 of Sec. 1065.205. Note that your 
balance-based system must meet the linearity verification in Sec. 
1065.307. If the balance uses an internal calibration process for 
routine spanning and linearity verifications, the process must be NIST-
traceable.
    (c) Loss correction. You may use PM loss corrections to account for 
PM loss in the inertial balance, including the sample handling system.
    (d) Deposition. You may use electrostatic deposition to collect PM 
as long as its collection efficiency is at least 95%.

[73 FR 59259, Oct. 8, 2008, as amended at 75 FR 68462, Nov. 8, 2010; 76 
FR 57443, Sept. 15, 2011; 79 FR 23762, Apr. 28, 2014]



                Subpart D_Calibrations and Verifications



Sec. 1065.301  Overview and general provisions.

    (a) This subpart describes required and recommended calibrations and 
verifications of measurement systems. See subpart C of this part for 
specifications that apply to individual instruments.
    (b) You must generally use complete measurement systems when 
performing calibrations or verifications in this subpart. For example, 
this would generally involve evaluating instruments based on values 
recorded with the complete system you use for recording test data, 
including analog-to-digital converters. For some calibrations and 
verifications, we may specify that you disconnect part of the 
measurement system to introduce a simulated signal.
    (c) If we do not specify a calibration or verification for a portion 
of a measurement system, calibrate that portion of your system and 
verify its performance at a frequency consistent with any 
recommendations from the measurement-system manufacturer, consistent 
with good engineering judgment.
    (d) Use NIST-traceable standards to the tolerances we specify for 
calibrations and verifications. Where we specify the need to use NIST-
traceable standards, you may alternatively ask for our approval to use 
international standards that are not NIST-traceable.



Sec. 1065.303  Summary of required calibration and verifications.

    The following table summarizes the required and recommended 
calibrations and verifications described in this subpart and indicates 
when these have to be performed:

[[Page 97]]



     Table 1 of Sec. 1065.303--Summary of Required Calibration and
                              Verifications
------------------------------------------------------------------------
 Type of calibration or verification         Minimum frequency \1\
------------------------------------------------------------------------
Sec. 1065.305: Accuracy,             Accuracy: Not required, but
 repeatability and noise.               recommended for initial
                                        installation.
                                       Repeatability: Not required, but
                                        recommended for initial
                                        installation.
                                       Noise: Not required, but
                                        recommended for initial
                                        installation.
Sec. 1065.307: Linearity             Speed: Upon initial installation,
 verification.                          within 370 days before testing
                                        and after major maintenance.
                                       Torque: Upon initial
                                        installation, within 370 days
                                        before testing and after major
                                        maintenance.
                                       Electrical power, current, and
                                        voltage: Upon initial
                                        installation, within 370 days
                                        before testing and after major
                                        maintenance.\2\
                                       Fuel flow rate: Upon initial
                                        installation, within 370 days
                                        before testing, and after major
                                        maintenance.
                                       DEF flow: Upon initial
                                        installation, within 370 days
                                        before testing, and after major
                                        maintenance.
                                       Intake-air, dilution air, diluted
                                        exhaust, and batch sampler flow
                                        rates: Upon initial
                                        installation, within 370 days
                                        before testing and after major
                                        maintenance, unless flow is
                                        verified by propane check or by
                                        carbon or oxygen balance.
                                       Raw exhaust flow rate: Upon
                                        initial installation, within 185
                                        days before testing and after
                                        major maintenance, unless flow
                                        is verified by propane check or
                                        by carbon or oxygen balance.
                                       Gas dividers: Upon initial
                                        installation, within 370 days
                                        before testing, and after major
                                        maintenance.
                                       Gas analyzers (unless otherwise
                                        noted): Upon initial
                                        installation, within 35 days
                                        before testing and after major
                                        maintenance.
                                       FTIR and photoacoustic analyzers:
                                        Upon initial installation,
                                        within 370 days before testing
                                        and after major maintenance.
                                       GC-ECD: Upon initial installation
                                        and after major maintenance.
                                       PM balance: Upon initial
                                        installation, within 370 days
                                        before testing and after major
                                        maintenance.
                                       Pressure, temperature, and
                                        dewpoint: Upon initial
                                        installation, within 370 days
                                        before testing and after major
                                        maintenance.
Sec. 1065.308: Continuous gas        Upon initial installation or
 analyzer system response and           after system modification that
 updating-recording verification--for   would affect response.
 gas analyzers not continuously
 compensated for other gas species.
Sec. 1065.309: Continuous gas        Upon initial installation or
 analyzer system-response and           after system modification that
 updating-recording verification--for   would affect response.
 gas analyzers continuously
 compensated for other gas species.
Sec. 1065.310: Torque..............  Upon initial installation and
                                        after major maintenance.
Sec. 1065.315: Pressure,             Upon initial installation and
 temperature, dewpoint.                 after major maintenance.
Sec. 1065.320: Fuel flow...........  Upon initial installation and
                                        after major maintenance.
Sec. 1065.325: Intake flow.........  Upon initial installation and
                                        after major maintenance.
Sec. 1065.330: Exhaust flow........  Upon initial installation and
                                        after major maintenance.
Sec. 1065.340: Diluted exhaust flow  Upon initial installation and
 (CVS).                                 after major maintenance.
Sec. 1065.341: CVS and batch         Upon initial installation, within
 sampler verification \3\.              35 days before testing, and
                                        after major maintenance.
Sec. 1065.342 Sample dryer           For thermal chillers: Upon
 verification.                          installation and after major
                                        maintenance.
                                       For osmotic membranes; Upon
                                        installation, within 35 days of
                                        testing, and after major
                                        maintenance.
Sec. 1065.345: Vacuum leak.........  For laboratory testing: Upon
                                        initial installation of the
                                        sampling system, within 8 hours
                                        before the start of the first
                                        test interval of each duty-cycle
                                        sequence, and after maintenance
                                        such as pre-filter changes.
                                       For field testing: After each
                                        installation of the sampling
                                        system on the vehicle, prior to
                                        the start of the field test, and
                                        after maintenance such as pre-
                                        filter changes.
Sec. 1065.350: CO2 NDIR H2O          Upon initial installation and
 interference.                          after major maintenance.
Sec. 1065.355: CO NDIR CO2 and H2O   Upon initial installation and
 interference.                          after major maintenance.
Sec. 1065.360: FID calibration THC   Calibrate all FID analyzers: Upon
 FID optimization, and THC FID          initial installation and after
 verification.                          major maintenance.
                                       Optimize and determine CH4
                                        response for THC FID analyzers:
                                        Upon initial installation and
                                        after major maintenance.
                                       Verify CH4 response for THC FID
                                        analyzers: Upon initial
                                        installation, within 185 days
                                        before testing, and after major
                                        maintenance.
                                       Verify C2H6 response for THC FID
                                        analyzers if used for NMNEHC
                                        determination: Upon initial
                                        installation, within 185 days
                                        before testing, and after major
                                        maintenance.
Sec. 1065.362: Raw exhaust FID O2    For all FID analyzers: Upon
 interference.                          initial installation, and after
                                        major maintenance.
                                       For THC FID analyzers: Upon
                                        initial installation, after
                                        major maintenance, and after FID
                                        optimization according to Sec.
                                        1065.360.
Sec. 1065.365: Nonmethane cutter     Upon initial installation, within
 penetration.                           185 days before testing, and
                                        after major maintenance.

[[Page 98]]

 
Sec. 1065.366: Interference          Upon initial installation and
 verification for FTIR analyzers.       after major maintenance.
Sec. 1065.369: H2O, CO, and CO2      Upon initial installation and
 interference verification for          after major maintenance.
 ethanol photoacoustic analyzers.
Sec. 1065.370: CLD CO2 and H2O       Upon initial installation and
 quench.                                after major maintenance.
Sec. 1065.372: NDUV HC and H2O       Upon initial installation and
 interference.                          after major maintenance.
Sec. 1065.375: N2O analyzer          Upon initial installation and
 interference.                          after major maintenance.
Sec. 1065.376: Chiller NO2           Upon initial installation and
 penetration.                           after major maintenance.
Sec. 1065.378: NO2-to-NO converter   Upon initial installation, within
 conversion.                            35 days before testing, and
                                        after major maintenance.
Sec. 1065.390: PM balance and        Independent verification: Upon
 weighing.                              initial installation, within 370
                                        days before testing, and after
                                        major maintenance.
                                       Zero, span, and reference sample
                                        verifications: Within 12 hours
                                        of weighing, and after major
                                        maintenance.
Sec. 1065.395: Inertial PM balance   Independent verification: Upon
 and weighing.                          initial installation, within 370
                                        days before testing, and after
                                        major maintenance.
                                       Other verifications: Upon initial
                                        installation and after major
                                        maintenance.
------------------------------------------------------------------------
\1\ Perform calibrations and verifications more frequently than we
  specify, according to measurement system manufacturer instructions and
  good engineering judgment.
\2\ Perform linearity verification either for electrical power or for
  current and voltage.
\3\ The CVS verification described in Sec. 1065.341 is not required
  for systems that agree within [2% based on a chemical balance of
  carbon or oxygen of the intake air, fuel, and diluted exhaust.


[81 FR 74164, Oct. 25, 2016]



Sec. 1065.305  Verifications for accuracy, repeatability,
and noise.

    (a) This section describes how to determine the accuracy, 
repeatability, and noise of an instrument. Table 1 of Sec. 1065.205 
specifies recommended values for individual instruments.
    (b) We do not require you to verify instrument accuracy, 
repeatability, or noise.
    However, it may be useful to consider these verifications to define 
a specification for a new instrument, to verify the performance of a new 
instrument upon delivery, or to troubleshoot an existing instrument.
    (c) In this section we use the letter ``y'' to denote a generic 
measured quantity, the superscript over-bar to denote an arithmetic mean 
(such as y), and the subscript ``ref'' to denote the reference quantity 
being measured.
    (d) Conduct these verifications as follows:
    (1) Prepare an instrument so it operates at its specified 
temperatures, pressures, and flows. Perform any instrument linearization 
or calibration procedures prescribed by the instrument manufacturer.
    (2) Zero the instrument as you would before an emission test by 
introducing a zero signal. Depending on the instrument, this may be a 
zero-concentration gas, a reference signal, a set of reference 
thermodynamic conditions, or some combination of these. For gas 
analyzers, use a zero gas that meets the specifications of Sec. 
1065.750.
    (3) Span the instrument as you would before an emission test by 
introducing a span signal. Depending on the instrument, this may be a 
span-concentration gas, a reference signal, a set of reference 
thermodynamic conditions, or some combination of these. For gas 
analyzers, use a span gas that meets the specifications of Sec. 
1065.750.
    (4) Use the instrument to quantify a NIST-traceable reference 
quantity, yref. For gas analyzers the reference gas must meet 
the specifications of Sec. 1065.750. Select a reference quantity near 
the mean value expected during testing. For all gas analyzers, use a 
quantity near the flow-weighted mean concentration expected at the 
standard or expected during testing, whichever is greater. For noise 
verification, use the same zero gas from paragraph (d)(2) of this 
section as the reference quantity. In all cases, allow time for the 
instrument to stabilize while it measures the reference quantity. 
Stabilization time may include time to purge an instrument and time to 
account for its response.

[[Page 99]]

    (5) Sample and record values for 30 seconds (you may select a longer 
sampling period if the recording update frequency is less than 0.5 Hz), 
record the arithmetic mean, yi and record the standard 
deviation, si of the recorded values. Refer to Sec. 1065.602 
for an example of calculating arithmetic mean and standard deviation.
    (6) Also, if the reference quantity is not absolutely constant, 
which might be the case with a reference flow, sample and record values 
of yrefi for 30 seconds and record the arithmetic mean of the 
values, yref. Refer to Sec. 1065.602 for an example of calculating 
arithmetic mean.
    (7) Subtract the reference value, yref (or 
yrefi), from the arithmetic mean, yi. Record this 
value as the error, [epsi] i.
    (8) Repeat the steps specified in paragraphs (d)(2) through (7) of 
this section until you have ten arithmetic means (y1, 
y2, yi, ...y10), ten standard 
deviations, (s 1, s 2, s i,...s 
10), and ten errors ([epsi] 1, [epsi] 
2, [epsi] i,...[epsi] 10).
    (9) Use the following values to quantify your measurements:
    (i) Accuracy. Instrument accuracy is the absolute difference between 
the reference quantity, yref (or yref), and the arithmetic mean of the 
ten yi, y values. Refer to the example of an accuracy calculation in 
Sec. 1065.602. We recommend that instrument accuracy be within the 
specifications in Table 1 of Sec. 1065.205.
    (ii) Repeatability. Repeatability is two times the standard 
deviation of the ten errors (that is, repeatability = 2 [middot] s[epsi] 
). Refer to the example of a standard-deviation calculation in Sec. 
1065.602. We recommend that instrument repeatability be within the 
specifications in Table 1 of Sec. 1065.205.
    (iii) Noise. Noise is two times the root-mean-square of the ten 
standard deviations (that is, noise = 2 [middot] rmss ) when the 
reference signal is a zero-quantity signal. Refer to the example of a 
root-mean-square calculation in Sec. 1065.602. We recommend that 
instrument noise be within the specifications in Table 1 of Sec. 
1065.205.
    (10) You may use a measurement instrument that does not meet the 
accuracy, repeatability, or noise specifications in Table 1 of Sec. 
1065.205, as long as you meet the following criteria:
    (i) Your measurement systems meet all the other required 
calibration, verification, and validation specifications that apply as 
specified in the regulations.
    (ii) The measurement deficiency does not adversely affect your 
ability to demonstrate compliance with the applicable standards.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37301, June 30, 2008; 
75 FR 23037, Apr. 30, 2010; 79 FR 23763, Apr. 28, 2014]



Sec. 1065.307  Linearity verification.

    (a) Scope and frequency. Perform linearity verification on each 
measurement system listed in Table 1 of this section at least as 
frequently as indicated in Table 1 of Sec. 1065.303, consistent with 
measurement system manufacturer's recommendations and good engineering 
judgment. The intent of linearity verification is to determine that a 
measurement system responds accurately and proportionally over the 
measurement range of interest. Linearity verification generally consists 
of introducing a series of at least 10 reference values to a measurement 
system. The measurement system quantifies each reference value. The 
measured values are then collectively compared to the reference values 
by using a least-squares linear regression and the linearity criteria 
specified in Table 1 of this section.
    (b) Performance requirements. If a measurement system does not meet 
the applicable linearity criteria referenced in Table 1 of this section, 
correct the deficiency by re-calibrating, servicing, or replacing 
components as needed. Repeat the linearity verification after correcting 
the deficiency to ensure that the measurement system meets the linearity 
criteria. Before you may use a measurement system that does not meet 
linearity criteria, you must demonstrate to us that the deficiency does 
not adversely affect your ability to demonstrate compliance with the 
applicable standards.
    (c) Procedure. Use the following linearity verification protocol, or 
use good engineering judgment to develop a different protocol that 
satisfies the intent of this section, as described in paragraph (a) of 
this section:

[[Page 100]]

    (1) In this paragraph (c), the letter ``y'' denotes a generic 
measured quantity, the superscript over-bar denotes an arithmetic mean 
(such as y), and the subscript ``ref'' denotes the known or 
reference quantity being measured.
    (2) Use good engineering judgment to operate a measurement system at 
normal operating conditions. This may include any specified adjustment 
or periodic calibration of the measurement system.
    (3) If applicable, zero the instrument as you would before an 
emission test by introducing a zero signal. Depending on the instrument, 
this may be a zero-concentration gas, a reference signal, a set of 
reference thermodynamic conditions, or some combination of these. For 
gas analyzers, use a zero gas that meets the specifications of Sec. 
1065.750 and introduce it directly at the analyzer port.
    (4) If applicable, span the instrument as you would before an 
emission test by introducing a span signal. Depending on the instrument, 
this may be a span-concentration gas, a reference signal, a set of 
reference thermodynamic conditions, or some combination of these. For 
gas analyzers, use a span gas that meets the specifications of Sec. 
1065.750 and introduce it directly at the analyzer port.
    (5) If applicable, after spanning the instrument, check zero with 
the same signal you used in paragraph (c)(3) of this section. Based on 
the zero reading, use good engineering judgment to determine whether or 
not to rezero and or re-span the instrument before continuing.
    (6) For all measured quantities, use the instrument manufacturer's 
recommendations and good engineering judgment to select reference 
values, yrefi, that cover a range of values that you expect would 
prevent extrapolation beyond these values during emission testing. We 
recommend selecting a zero reference signal as one of the reference 
values for the linearity verification. For pressure, temperature, 
dewpoint, power, current, voltage, photoacoustic analyzers, and GC-ECD 
linearity verifications, we recommend at least three reference values. 
For all other linearity verifications select at least ten reference 
values.
    (7) Use the instrument manufacturer's recommendations and good 
engineering judgment to select the order in which you will introduce the 
series of reference values. For example, you may select the reference 
values randomly to avoid correlation with previous measurements and to 
avoid hysteresis; you may select reference values in ascending or 
descending order to avoid long settling times of reference signals; or 
you may select values to ascend and then descend to incorporate the 
effects of any instrument hysteresis into the linearity verification.
    (8) Generate reference quantities as described in paragraph (d) of 
this section. For gas analyzers, use gas concentrations known to be 
within the specifications of Sec. 1065.750 and introduce them directly 
at the analyzer port.
    (9) Introduce a reference signal to the measurement instrument.
    (10) Allow time for the instrument to stabilize while it measures 
the value at the reference condition. Stabilization time may include 
time to purge an instrument and time to account for its response.
    (11) At a recording frequency of at least f Hz, specified in Table 1 
of Sec. 1065.205, measure the value at the reference condition for 30 
seconds (you may select a longer sampling period if the recording update 
frequency is less than 0.5 Hz) and record the arithmetic mean of the 
recorded values, yi. Refer to Sec. 1065.602 for an example 
of calculating an arithmetic mean.
    (12) Repeat the steps in paragraphs (c)(9) though (11) of this 
section until measurements are complete at each of the reference 
conditions.
    (13) Use the arithmetic means, yi, and reference values, yrefi, to 
calculate least-squares linear regression parameters and statistical 
values to compare to the minimum performance criteria specified in Table 
1 of this section. Use the calculations described in Sec. 1065.602. 
Using good engineering judgment, you may weight the results of 
individual data pairs (i.e. (yrefi, yi,)), in the linear 
regression calculations.

[[Page 101]]

    (d) Reference signals. This paragraph (d) describes recommended 
methods for generating reference values for the linearity-verification 
protocol in paragraph (c) of this section. Use reference values that 
simulate actual values, or introduce an actual value and measure it with 
a reference-measurement system. In the latter case, the reference value 
is the value reported by the reference-measurement system. Reference 
values and reference-measurement systems must be NIST-traceable. We 
recommend using calibration reference quantities that are NIST-traceable 
within 0.5% uncertainty, if not specified elsewhere in this part 1065. 
Use the following recommended methods to generate reference values or 
use good engineering judgment to select a different reference:
    (1) Speed. Run the engine or dynamometer at a series of steady-state 
speeds and use a strobe, photo tachometer, or laser tachometer to record 
reference speeds.
    (2) Torque. Use a series of calibration weights and a calibration 
lever arm to simulate engine torque. You may instead use the engine or 
dynamometer itself to generate a nominal torque that is measured by a 
reference load cell or proving ring in series with the torque-
measurement system. In this case, use the reference load cell 
measurement as the reference value. Refer to Sec. 1065.310 for a 
torque-calibration procedure similar to the linearity verification in 
this section.
    (3) Electrical power, current, and voltage. You must perform 
linearity verification for either electrical power meters, or for 
current and voltage meters. Perform linearity verifications using a 
reference meter and controlled sources of current and voltage. We 
recommend using a complete calibration system that is suitable for the 
electrical power distribution industry.
    (4) Fuel rate. Operate the engine at a series of constant fuel-flow 
rates or re-circulate fuel back to a tank through the fuel flow meter at 
different flow rates. Use a gravimetric reference measurement (such as a 
scale, balance, or mass comparator) at the inlet to the fuel-measurement 
system. Use a stopwatch or timer to measure the time intervals over 
which reference masses of fuel are introduced to the fuel measurement 
system. The reference fuel mass divided by the time interval is the 
reference fuel flow rate.
    (5) Flow rates--inlet air, dilution air, diluted exhaust, raw 
exhaust, or sample flow. Use a reference flow meter with a blower or 
pump to simulate flow rates. Use a restrictor, diverter valve, a 
variable-speed blower or a variable-speed pump to control the range of 
flow rates. Use the reference meter's response as the reference values.
    (i) Reference flow meters. Because the flow range requirements for 
these various flows are large, we allow a variety of reference meters. 
For example, for diluted exhaust flow for a full-flow dilution system, 
we recommend a reference subsonic venturi flow meter with a restrictor 
valve and a blower to simulate flow rates. For inlet air, dilution air, 
diluted exhaust for partial-flow dilution, raw exhaust, or sample flow, 
we allow reference meters such as critical flow orifices, critical flow 
venturis, laminar flow elements, master mass flow standards, or Roots 
meters. Make sure the reference meter is calibrated and its calibration 
is NIST-traceable. If you use the difference of two flow measurements to 
determine a net flow rate, you may use one of the measurements as a 
reference for the other.
    (ii) Reference flow values. Because the reference flow is not 
absolutely constant, sample and record values of nrefi for 30 
seconds and use the arithmetic mean of the values, nref, as 
the reference value. Refer to Sec. 1065.602 for an example of 
calculating arithmetic mean.
    (6) Gas division. Use one of the two reference signals:
    (i) At the outlet of the gas-division system, connect a gas analyzer 
that meets the linearity verification described in this section and has 
not been linearized with the gas divider being verified. For example, 
verify the linearity of an analyzer using a series of reference 
analytical gases directly from compressed gas cylinders that meet the 
specifications of Sec. 1065.750. We recommend using a FID analyzer or a 
PMD or MPD O2 analyzer because of their inherent linearity. 
Operate this analyzer consistent with how you

[[Page 102]]

would operate it during an emission test. Connect a span gas to the gas-
divider inlet. Use the gas-division system to divide the span gas with 
purified air or nitrogen. Select gas divisions that you typically use. 
Use a selected gas division as the measured value. Use the analyzer 
response divided by the span gas concentration as the reference gas-
division value. Because the instrument response is not absolutely 
constant, sample and record values of xref for 30 seconds and 
use the arithmetic mean of the values, xref, as the reference 
value. Refer to Sec. 1065.602 for an example of calculating arithmetic 
mean.
    (ii) Using good engineering judgment and the gas divider 
manufacturer's recommendations, use one or more reference flow meters to 
measure the flow rates of the gas divider and verify the gas-division 
value.
    (7) Continuous constituent concentration. For reference values, use 
a series of gas cylinders of known gas concentration or use a gas-
division system that is known to be linear with a span gas. Gas 
cylinders, gas-division systems, and span gases that you use for 
reference values must meet the specifications of Sec. 1065.750.
    (8) Temperature. You may perform the linearity verification for 
temperature measurement systems with thermocouples, RTDs, and 
thermistors by removing the sensor from the system and using a simulator 
in its place. Use a NIST-traceable simulator that is independently 
calibrated and, as appropriate, cold-junction-compensated. The simulator 
uncertainty scaled to absolute temperature must be less than 0.5% of 
Tmax. If you use this option, you must use sensors that the 
supplier states are accurate to better than 0.5% of Tmax 
compared with their standard calibration curve.
    (9) Mass. For linearity verification for gravimetric PM balances, 
use external calibration weights that meet the requirements in Sec. 
1065.790.
    (e) Measurement systems that require linearity verification. Table 1 
of this section indicates measurement systems that require linearity 
verification, subject to the following provisions:
    (1) Perform linearity verification more frequently based on the 
instrument manufacturer's recommendation or good engineering judgment.
    (2) The expression ``xmin'' refers to the reference value 
used during linearity verification that is closest to zero. This is the 
value used to calculate the first tolerance in Table 1 of this section 
using the intercept, a0. Note that this value may be zero, 
positive, or negative depending on the reference values. For example, if 
the reference values chosen to validate a pressure transducer vary from 
-10 to -1 kPa, xmin is -1 kPa. If the reference values used 
to validate a temperature device vary from 290 to 390 K, xmin 
is 290 K.
    (3) The expression ``max'' generally refers to the absolute value of 
the reference value used during linearity verification that is furthest 
from zero. This is the value used to scale the first and third 
tolerances in Table 1 of this section using a0 and SEE. For 
example, if the reference values chosen to validate a pressure 
transducer vary from -10 to -1 kPa, then pmax is + 10 kPa. If 
the reference values used to validate a temperature device vary from 290 
to 390 K, then Tmax is 390 K. For gas dividers where ``max'' 
is expressed as, xmax/xspan; xmax is 
the maximum gas concentration used during the verification, 
xspan is the undivided, undiluted, span gas concentration, 
and the resulting ratio is the maximum divider point reference value 
used during the verification (typically 1). The following are special 
cases where ``max'' refers to a different value:
    (i) For linearity verification with a PM balance, mmax 
refers to the typical mass of a PM filter.
    (ii) For linearity verification of torque on the engine's primary 
output shaft, Tmax refers to the manufacturer's specified 
engine torque peak value of the lowest torque engine to be tested.
    (4) The specified ranges are inclusive. For example, a specified 
range of 0.98-1.02 for a1 means 0.98<=a1<=1.02.
    (5) Linearity verification is optional for systems that pass the 
flow-rate verification for diluted exhaust as described in Sec. 
1065.341 (the propane check) or for systems that agree within [2% based 
on a chemical balance of carbon or oxygen of the intake air, fuel, and 
exhaust.

[[Page 103]]

    (6) You must meet the a1 criteria for these quantities 
only if the absolute value of the quantity is required, as opposed to a 
signal that is only linearly proportional to the actual value.
    (7) Linearity verification is required for the following temperature 
measurements:
    (i) The following temperature measurements always require linearity 
verification:
    (A) Air intake.
    (B) Aftertreatment bed(s), for engines tested with aftertreatment 
devices subject to cold-start testing.
    (C) Dilution air for gaseous and PM sampling, including CVS, double-
dilution, and partial-flow systems.
    (D) PM sample.
    (E) Chiller sample, for gaseous sampling systems that use thermal 
chillers to dry samples and use chiller temperature to calculate the 
dewpoint at the outlet of the chiller. For your testing, if you choose 
to use a high alarm temperature setpoint for the chiller temperature as 
a constant value in determining the amount of water removed from the 
emission sample, you may use good engineering judgment to verify the 
accuracy of the high alarm temperature setpoint instead of linearity 
verification on the chiller temperature. To verify that the alarm trip 
point value is no less than 2.0  deg.C below the reference value at the 
trip point, we recommend that you input a reference simulated 
temperature signal below the alarm trip point and increase this signal 
until the high alarm trips.
    (ii) Linearity verification is required for the following 
temperature measurements if these temperature measurements are specified 
by the engine manufacturer:
    (A) Fuel inlet.
    (B) Air outlet to the test cell's charge air cooler air outlet, for 
engines tested with a laboratory heat exchanger that simulates an 
installed charge air cooler.
    (C) Coolant inlet to the test cell's charge air cooler, for engines 
tested with a laboratory heat exchanger that simulates an installed 
charge air cooler.
    (D) Oil in the sump/pan.
    (E) Coolant before the thermostat, for liquid-cooled engines.
    (8) Linearity verification is required for the following pressure 
measurements:
    (i) The following pressure measurements always require linearity 
verification:
    (A) Air intake restriction.
    (B) Exhaust back pressure as required in Sec. 1065.130(h).
    (C) Barometer.
    (D) CVS inlet gage pressure where the raw exhaust enters the tunnel.
    (E) Sample dryer, for gaseous sampling systems that use either 
osmotic-membrane or thermal chillers to dry samples. For your testing, 
if you choose to use a low alarm pressure setpoint for the sample dryer 
pressure as a constant value in determining the amount of water removed 
from the emission sample, you may use good engineering judgment to 
verify the accuracy of the low alarm pressure setpoint instead of 
linearity verification on the sample dryer pressure. To verify that the 
trip point value is no more than 4.0 kPa above the reference value at 
the trip point, we recommend that you input a reference pressure signal 
above the alarm trip point and decrease this signal until the low alarm 
trips.
    (ii) Linearity verification is required for the following pressure 
measurements if these pressure measurements are specified by the engine 
manufacturer:
    (A) The test cell's charge air cooler and interconnecting pipe 
pressure drop, for turbo-charged engines tested with a laboratory heat 
exchanger that simulates an installed charge air cooler.
    (B) Fuel outlet.

               Table 1 of Sec. 1065.307--Measurement Systems That Require Linearity Verification
----------------------------------------------------------------------------------------------------------------
                                                                        Linearity criteria
                                                ----------------------------------------------------------------
      Measurement system            Quantity      | xmin(a1-
                                                  1) + a 0|        a1             SEE            r \2\
----------------------------------------------------------------------------------------------------------------
Speed.........................  fn.............  <=0.05% [middot]      0.98-1.02  <=2% [middot]          >=0.990
                                                  fnmax.                           fnmax.
Torque........................  T..............  <=1% [middot] Tmax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   Tmax.
Electrical power..............  P..............  <=1% [middot] Pmax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   Pmax
Current.......................  I..............  <=1% [middot] Imax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   Imax

[[Page 104]]

 
Voltage.......................  U..............  <=1% [middot] Umax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   Umax.
Fuel flow rate................  m..............  <=1% [middot] mmax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   mmax.
Intake-air....................  n..............  <=1% [middot] nmax    0.98-1.02  <=2% [middot]          >=0.990
 flow rate\1\.................                                                     nmax.
Dilution air flow rate \1\....  n..............  <=1% [middot] nmax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   nmax.
Diluted exhaust flow rate \1\.  n..............  <=1% [middot] nmax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   nmax.
Raw exhaust flow rate \1\.....  n..............  <=1% [middot] nmax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   nmax.
Batch sampler flow rates \1\..  n..............  <=1% [middot] nmax    0.98-1.02  <=2% [middot]          >=0.990
                                                                                   nmax.
Gas dividers..................  x/xspan........  <=0.5% [middot]       0.98-1.02  <=2% [middot]          >=0.990
                                                  xmax/xspan.                      xmax/xspan.
Gas analyzers for laboratory    x..............  <=0.5% [middot]       0.99-1.01  <=1% [middot]          >=0.998
 testing.                                         xmax.                            xmax.
Gas analyzers for field         x..............  <=1% [middot] xmax    0.99-1.01  <=1% [middot]          >=0.998
 testing.                                                                          xmax.
PM balance....................  m..............  <=1% [middot] mmax    0.99-1.01  <=1% [middot]          >=0.998
                                                                                   mmax.
Pressures.....................  p..............  <=1% [middot] pmax    0.99-1.01  <=1% [middot]          >=0.998
                                                                                   pmax.
Dewpoint for intake air, PM-    Tdew...........  <=0.5% [middot]       0.99-1.01  <=0.5% [middot]        >=0.998
 stabilization and balance                        Tdewmax.                         Tdewmax.
 environments.
Other dewpoint measurements...  Tdew...........  <=1% [middot]         0.99-1.01  <=1% [middot]          >=0.998
                                                  Tdewmax-.                        Tdewmax-.
Analog-to-digital conversion    T..............  <=1% [middot] Tmax    0.99-1.01  <=1% [middot]          >=0.998
 of temperature signals.                                                           Tmax.
----------------------------------------------------------------------------------------------------------------
\1\ For flow meters that determine volumetric flow rate, Vstd, you may substitute Vstd for n as the quantity and
  substitute Vstdmax for nmax.

[79 FR 23763, Apr. 28, 2014]



Sec. 1065.308  Continuous gas analyzer system-response and updating-
recording verification--for gas analyzers not continuously compensated
for other gas species.

    (a) Scope and frequency. This section describes a verification 
procedure for system response and updating-recording frequency for 
continuous gas analyzers that output a gas species mole fraction (i.e., 
concentration) using a single gas detector, i.e., gas analyzers not 
continuously compensated for other gas species measured with multiple 
gas detectors. See Sec. 1065.309 for verification procedures that apply 
to continuous gas analyzers that are continuously compensated for other 
gas species measured with multiple gas detectors. Perform this 
verification to determine the system response of the continuous gas 
analyzer and its sampling system. This verification is required for 
continuous gas analyzers used for transient or ramped-modal testing. You 
need not perform this verification for batch gas analyzer systems or for 
continuous gas analyzer systems that are used only for discrete-mode 
testing. Perform this verification after initial installation (i.e., 
test cell commissioning) and after any modifications to the system that 
would change system response. For example, perform this verification if 
you add a significant volume to the transfer lines by increasing their 
length or adding a filter; or if you reduce the frequency at which the 
gas analyzer updates its output or the frequency at which you sample and 
record gas-analyzer concentrations.
    (b) Measurement principles. This test verifies that the updating and 
recording frequencies match the overall system response to a rapid 
change in the value of concentrations at the sample probe. Gas analyzers 
and their sampling systems must be optimized such that their overall 
response to a rapid change in concentration is updated and recorded at 
an appropriate frequency to prevent loss of information. This test also 
verifies that the measurement system meets a minimum response time. You 
may use the results of this test to determine transformation time, 
t50, for the purposes of time alignment of continuous data in 
accordance with Sec. 1065.650(c)(2)(i). You may also use an alternate 
procedure to determine t50 in accordance with good 
engineering judgment. Note that any such procedure for determining 
t50 must account for both transport delay and analyzer 
response time.

[[Page 105]]

    (c) System requirements. Demonstrate that each continuous analyzer 
has adequate update and recording frequencies and has a minimum rise 
time and a minimum fall time during a rapid change in gas concentration. 
You must meet one of the following criteria:
    (1) The product of the mean rise time, t10-90, and the 
frequency at which the system records an updated concentration must be 
at least 5, and the product of the mean fall time, t90-10, 
and the frequency at which the system records an updated concentration 
must be at least 5. If the recording frequency is different than the 
analyzer's output update frequency, you must use the lower of these two 
frequencies for this verification, which is referred to as the updating-
recording frequency. This verification applies to the nominal updating 
and recording frequencies. This criterion makes no assumption regarding 
the frequency content of changes in emission concentrations during 
emission testing; therefore, it is valid for any testing. Also, the mean 
rise time must be at or below 10 seconds and the mean fall time must be 
at or below 10 seconds.
    (2) The frequency at which the system records an updated 
concentration must be at least 5 Hz. This criterion assumes that the 
frequency content of significant changes in emission concentrations 
during emission testing do not exceed 1 Hz. Also, the mean rise time 
must be at or below 10 seconds and the mean fall time must be at or 
below 10 seconds.
    (3) You may use other criteria if we approve the criteria in 
advance.
    (4) You may meet the overall PEMS verification in Sec. 1065.920 
instead of the verification in this section for field testing with PEMS.
    (d) Procedure. Use the following procedure to verify the response of 
each continuous gas analyzer:
    (1) Instrument setup. Follow the analyzer manufacturer's start-up 
and operating instructions. Adjust the measurement system as needed to 
optimize performance. Run this verification with the analyzer operating 
in the same manner you will use for emission testing. If the analyzer 
shares its sampling system with other analyzers, and if gas flow to the 
other analyzers will affect the system response time, then start up and 
operate the other analyzers while running this verification test. You 
may run this verification test on multiple analyzers sharing the same 
sampling system at the same time. If you use any analog or real-time 
digital filters during emission testing, you must operate those filters 
in the same manner during this verification.
    (2) Equipment setup. We recommend using minimal lengths of gas 
transfer lines between all connections and fast-acting three-way valves 
(2 inlets, 1 outlet) to control the flow of zero and blended span gases 
to the sample system's probe inlet or a tee near the outlet of the 
probe. If you inject the gas at a tee near the outlet of the probe, you 
may correct the transformation time, t50, for an estimate of 
the transport time from the probe inlet to the tee. Normally the gas 
flow rate is higher than the sample flow rate and the excess is 
overflowed out the inlet of the probe. If the gas flow rate is lower 
than the sample flow rate, the gas concentrations must be adjusted to 
account for the dilution from ambient air drawn into the probe. We 
recommend you use the final, stabilized analyzer reading as the final 
gas concentration. Select span gases for the species being measured. You 
may use binary or multi-gas span gases. You may use a gas blending or 
mixing device to blend span gases. A gas blending or mixing device is 
recommended when blending span gases diluted in N2 with span 
gases diluted in air. You may use a multi-gas span gas, such as NO-CO-
CO2-C3H8-CH4, to verify 
multiple analyzers at the same time. If you use standard binary span 
gases, you must run separate response tests for each analyzer. In 
designing your experimental setup, avoid pressure pulsations due to 
stopping the flow through the gas-blending device. The change in gas 
concentration must be at least 20% of the analyzer's range.
    (3) Data collection. (i) Start the flow of zero gas.
    (ii) Allow for stabilization, accounting for transport delays and 
the slowest analyzer's full response.
    (iii) Start recording data. For this verification you must record 
data at a frequency greater than or equal to that

[[Page 106]]

of the updating-recording frequency used during emission testing. You 
may not use interpolation or filtering to alter the recorded values.
    (iv) Switch the flow to allow the blended span gases to flow to the 
analyzer. If you intend to use the data from this test to determine 
t50 for time alignment, record this time as t0.
    (v) Allow for transport delays and the slowest analyzer's full 
response.
    (vi) Switch the flow to allow zero gas to flow to the analyzer. If 
you intend to use the data from this test to determine t50 
for time alignment, record this time as t100.
    (vii) Allow for transport delays and the slowest analyzer's full 
response.
    (viii) Repeat the steps in paragraphs (d)(3)(iv) through (vii) of 
this section to record seven full cycles, ending with zero gas flowing 
to the analyzers.
    (ix) Stop recording.
    (e) Performance evaluation. (1) If you choose to demonstrate 
compliance with paragraph (c)(1) of this section, use the data from 
paragraph (d)(3) of this section to calculate the mean rise time, 
t10-90, and mean fall time, t90-10, for each of 
the analyzers being verified. You may use interpolation between recorded 
values to determine rise and fall times. If the recording frequency used 
during emission testing is different from the analyzer's output update 
frequency, you must use the lower of these two frequencies for this 
verification. Multiply these times (in seconds) by their respective 
updating-recording frequencies in Hertz (1/second). The resulting 
product must be at least 5 for both rise time and fall time. If either 
value is less than 5, increase the updating-recording frequency, or 
adjust the flows or design of the sampling system to increase the rise 
time and fall time as needed. You may also configure analog or digital 
filters before recording to increase rise and fall times. In no case may 
the mean rise time or mean fall time be greater than 10 seconds.
    (2) If a measurement system fails the criterion in paragraph (e)(1) 
of this section, ensure that signals from the system are updated and 
recorded at a frequency of at least 5 Hz. In no case may the mean rise 
time or mean fall time be greater than 10 seconds.
    (3) If a measurement system fails the criteria in paragraphs (e)(1) 
and (2) of this section, you may use the measurement system only if the 
deficiency does not adversely affect your ability to show compliance 
with the applicable standards.
    (f) Transformation time, t50, determination. If you 
choose to determine t50 for purposes of time alignment using 
data generated in paragraph (d)(3) of this section, calculate the mean 
t0-50 and the mean t100-50 from the recorded data. 
Average these two values to determine the final t50 for the 
purposes of time alignment in accordance with Sec. 1065.650(c)(2)(i).
    (g) Optional procedure. Instead of using a three-way valve to switch 
between zero and span gases, you may use a fast-acting two-way valve to 
switch sampling between ambient air and span gas at the probe inlet. For 
this alternate procedure, the following provisions apply:
    (1) If your probe is sampling from a continuously flowing gas stream 
(e.g., a CVS tunnel), you may adjust the span gas flow rate to be 
different than the sample flow rate.
    (2) If your probe is sampling from a gas stream that is not 
continuously flowing (e.g., a raw exhaust stack), you must adjust the 
span gas flow rate to be less than the sample flow rate so ambient air 
is always being drawn into the probe inlet. This avoids errors 
associated with overflowing span gas out of the probe inlet and drawing 
it back in when sampling ambient air.
    (3) When sampling ambient air or ambient air mixed with span gas, 
all the analyzer readings must be stable within [0.5% of the target gas 
concentration step size. If any analyzer reading is outside the 
specified range, you must resolve the problem and verify that all the 
analyzer readings meet this specification.
    (4) For oxygen analyzers, you may use purified N2 as the 
zero gas and ambient air (plus purified N2 if needed) as the 
reference gas. Perform the verification with seven repeat measurements 
that each consist of stabilizing with purified N2, switching 
to ambient air and observing the analyzer's rise and stabilized reading, 
followed by switching back to purified N2

[[Page 107]]

and observing the analyzer's fall and stabilized reading.

[73 FR 59325, Oct. 8, 2008, as amended at 79 FR 23766, Apr. 28, 2014]



Sec. 1065.309  Continuous gas analyzer system-response and updating-
recording verification--for gas analyzers continuously compensated 
for other gas species.

    (a) Scope and frequency. This section describes a verification 
procedure for system response and updating-recording frequency for 
continuous gas analyzers that output a single gas species mole fraction 
(i.e., concentration) based on a continuous combination of multiple gas 
species measured with multiple detectors (i.e., gas analyzers 
continuously compensated for other gas species). See Sec. 1065.308 for 
verification procedures that apply to continuous gas analyzers that are 
not continuously compensated for other gas species or that use only one 
detector for gaseous species. Perform this verification to determine the 
system response of the continuous gas analyzer and its sampling system. 
This verification is required for continuous gas analyzers used for 
transient or ramped-modal testing. You need not perform this 
verification for batch gas analyzers or for continuous gas analyzers 
that are used only for discrete-mode testing. For this check we consider 
water vapor a gaseous constituent. This verification does not apply to 
any processing of individual analyzer signals that are time-aligned to 
their t50 times and were verified according to Sec. 
1065.308. For example, this verification does not apply to correction 
for water removed from the sample done in post-processing according to 
Sec. 1065.659 (40 CFR 1066.620 for vehicle testing) and it does not 
apply to NMHC determination from THC and CH4 according to 
Sec. 1065.660. Perform this verification after initial installation 
(i.e., test cell commissioning) and after any modifications to the 
system that would change the system response.
    (b) Measurement principles. This procedure verifies that the 
updating and recording frequencies match the overall system response to 
a rapid change in the value of concentrations at the sample probe. It 
indirectly verifies the time-alignment and uniform response of all the 
continuous gas detectors used to generate a continuously combined/
compensated concentration measurement signal. Gas analyzer systems must 
be optimized such that their overall response to rapid change in 
concentration is updated and recorded at an appropriate frequency to 
prevent loss of information. This test also verifies that the 
measurement system meets a minimum response time. For this procedure, 
ensure that all compensation algorithms and humidity corrections are 
turned on. You may use the results of this test to determine 
transformation time, t50, for the purposes of time alignment 
of continuous data in accordance with Sec. 1065.650(c)(2)(i). You may 
also use an alternate procedure to determine t50 consistent 
with good engineering judgment. Note that any such procedure for 
determining t50 must account for both transport delay and 
analyzer response time.
    (c) System requirements. Demonstrate that each continuously 
combined/compensated concentration measurement has adequate updating and 
recording frequencies and has a minimum rise time and a minimum fall 
time during a system response to a rapid change in multiple gas 
concentrations, including H2O concentration if H2O 
compensation is applied. You must meet one of the following criteria:
    (1) The product of the mean rise time, t10-90, and the 
frequency at which the system records an updated concentration must be 
at least 5, and the product of the mean fall time, t90-10, 
and the frequency at which the system records an updated concentration 
must be at least 5. If the recording frequency is different than the 
update frequency of the continuously combined/compensated signal, you 
must use the lower of these two frequencies for this verification. This 
criterion makes no assumption regarding the frequency content of changes 
in emission concentrations during emission testing; therefore, it is 
valid for any testing. Also, the mean rise time must be at or below 10 
seconds and the mean fall time must be at or below 10 seconds.
    (2) The frequency at which the system records an updated 
concentration

[[Page 108]]

must be at least 5 Hz. This criterion assumes that the frequency content 
of significant changes in emission concentrations during emission 
testing do not exceed 1 Hz. Also, the mean rise time must be at or below 
10 seconds and the mean fall time must be at or below 10 seconds.
    (3) You may use other criteria if we approve them in advance.
    (4) You may meet the overall PEMS verification in Sec. 1065.920 
instead of the verification in this section for field testing with PEMS.
    (d) Procedure. Use the following procedure to verify the response of 
each continuously compensated analyzer (verify the combined signal, not 
each individual continuously combined concentration signal):
    (1) Instrument setup. Follow the analyzer manufacturer's start-up 
and operating instructions. Adjust the measurement system as needed to 
optimize performance. Run this verification with the analyzer operating 
in the same manner you will use for emission testing. If the analyzer 
shares its sampling system with other analyzers, and if gas flow to the 
other analyzers will affect the system response time, then start up and 
operate the other analyzers while running this verification test. You 
may run this verification test on multiple analyzers sharing the same 
sampling system at the same time. If you use any analog or real-time 
digital filters during emission testing, you must operate those filters 
in the same manner during this verification.
    (2) Equipment setup. We recommend using minimal lengths of gas 
transfer lines between all connections and fast-acting three-way valves 
(2 inlets, 1 outlet) to control the flow of zero and blended span gases 
to the sample system's probe inlet or a tee near the outlet of the 
probe. If you inject the gas at a tee near the outlet of the probe, you 
may correct the transformation time, t50, for an estimate of 
the transport time from the probe inlet to the tee. Normally the gas 
flow rate is higher than the sample flow rate and the excess is 
overflowed out the inlet of the probe. If the gas flow rate is lower 
than the sample flow rate, the gas concentrations must be adjusted to 
account for the dilution from ambient air drawn into the probe. We 
recommend you use the final, stabilized analyzer reading as the final 
gas concentration. Select span gases for the species being continuously 
combined, other than H2O. Select concentrations of 
compensating species that will yield concentrations of these species at 
the analyzer inlet that covers the range of concentrations expected 
during testing. You may use binary or multi-gas span gases. You may use 
a gas blending or mixing device to blend span gases. A gas blending or 
mixing device is recommended when blending span gases diluted in 
N2 with span gases diluted in air. You may use a multi-gas 
span gas, such as NO-CO-CO2-C3H8-
CH4, to verify multiple analyzers at the same time. In 
designing your experimental setup, avoid pressure pulsations due to 
stopping the flow through the gas blending device. The change in gas 
concentration must be at least 20% of the analyzer's range. If 
H2O correction is applicable, then span gases must be 
humidified before entering the analyzer; however, you may not humidify 
NO2 span gas by passing it through a sealed humidification 
vessel that contains water. You must humidify NO2 span gas 
with another moist gas stream. We recommend humidifying your NO-CO-
CO2-C3H8-CH4, balance 
N2 blended gas by flowing the gas mixture through a sealed 
vessel that humidifies the gas by bubbling it through distilled water 
and then mixing the gas with dry NO2 gas, balance purified 
air. If your system does not use a sample dryer to remove water from the 
sample gas, you must humidify your span gas to the highest sample 
H2O content that you estimate during emission sampling. If 
your system uses a sample dryer during testing, it must pass the sample 
dryer verification check in Sec. 1065.342, and you must humidify your 
span gas to an H2O content greater than or equal to the level 
determined in Sec. 1065.145(e)(2). If you are humidifying span gases 
without NO2, use good engineering judgment to ensure that the 
wall temperatures in the transfer lines, fittings, and valves from the 
humidifying system to the probe are above the dewpoint required for the 
target H2O content. If you are humidifying span gases with 
NO2, use good engineering judgment to

[[Page 109]]

ensure that there is no condensation in the transfer lines, fittings, or 
valves from the point where humidified gas is mixed with NO2 
span gas to the probe. We recommend that you design your setup so that 
the wall temperatures in the transfer lines, fittings, and valves from 
the humidifying system to the probe are at least 5  deg.C above the 
local sample gas dewpoint. Operate the measurement and sample handling 
system as you do for emission testing. Make no modifications to the 
sample handling system to reduce the risk of condensation. Flow 
humidified gas through the sampling system before this check to allow 
stabilization of the measurement system's sampling handling system to 
occur, as it would for an emission test.
    (3) Data collection. (i) Start the flow of zero gas.
    (ii) Allow for stabilization, accounting for transport delays and 
the slowest analyzer's full response.
    (iii) Start recording data. For this verification you must record 
data at a frequency greater than or equal to that of the updating-
recording frequency used during emission testing. You may not use 
interpolation or filtering to alter the recorded values.
    (iv) Switch the flow to allow the blended span gases to flow to the 
analyzer. If you intend to use the data from this test to determine 
t50 for time alignment, record this time as t0.
    (v) Allow for transport delays and the slowest analyzer's full 
response.
    (vi) Switch the flow to allow zero gas to flow to the analyzer. If 
you intend to use the data from this test to determine t50 
for time alignment, record this time as t100.
    (vii) Allow for transport delays and the slowest analyzer's full 
response.
    (viii) Repeat the steps in paragraphs (d)(3)(iv) through (vii) of 
this section to record seven full cycles, ending with zero gas flowing 
to the analyzers.
    (ix) Stop recording.
    (e) Performance evaluations. (1) If you choose to demonstrate 
compliance with paragraph (c)(1) of this section, use the data from 
paragraph (d)(3) of this section to calculate the mean rise time, 
t10-90, and mean fall time, t90-10, for the 
continuously combined signal from each analyzer being verified. You may 
use interpolation between recorded values to determine rise and fall 
times. If the recording frequency used during emission testing is 
different from the analyzer's output update frequency, you must use the 
lower of these two frequencies for this verification. Multiply these 
times (in seconds) by their respective updating-recording frequencies in 
Hz (1/second). The resulting product must be at least 5 for both rise 
time and fall time. If either value is less than 5, increase the 
updating-recording frequency or adjust the flows or design of the 
sampling system to increase the rise time and fall time as needed. You 
may also configure analog or digital filters before recording to 
increase rise and fall times. In no case may the mean rise time or mean 
fall time be greater than 10 seconds.
    (2) If a measurement system fails the criterion in paragraph (e)(1) 
of this section, ensure that signals from the system are updated and 
recorded at a frequency of at least 5 Hz. In no case may the mean rise 
time or mean fall time be greater than 10 seconds.
    (3) If a measurement system fails the criteria in paragraphs (e)(1) 
and (2) of this section, you may use the measurement system only if the 
deficiency does not adversely affect your ability to show compliance 
with the applicable standards.
    (f) Transformation time, t50, determination. If you 
choose to determine t50 for purposes of time alignment using 
data generated in paragraph (d)(3) of this section, calculate the mean 
t0-50 and the mean t100-50 from the recorded data. 
Average these two values to determine the final t50 for the 
purposes of time alignment in accordance with Sec. 1065.650(c)(2)(i).
    (g) Optional procedure. Follow the optional procedures in Sec. 
1065.308(g), noting that you may use compensating gases mixed with 
ambient air for oxygen analyzers.
    (h) Analyzers with H2O compensation sampling downstream of a sample 
dryer. You may omit humidifying the span gas as described in this 
paragraph (h). If an analyzer compensates only for H2O, you 
may apply the requirements of Sec. 1065.308 instead of the requirements

[[Page 110]]

of this section. You may omit humidifying the span gas if you meet the 
following conditions:
    (1) The analyzer is located downstream of a sample dryer.
    (2) The maximum value for H2O mole fraction downstream of 
the dryer must be less than or equal to 0.010. Verify this during each 
sample dryer verification according to Sec. 1065.342.

[73 FR 59326, Oct. 8, 2008, as amended at 75 FR 23039, Apr. 30, 2010; 79 
FR 23767, Apr. 28, 2014]

         Measurement of Engine Parameters and Ambient Conditions



Sec. 1065.310  Torque calibration.

    (a) Scope and frequency. Calibrate all torque-measurement systems 
including dynamometer torque measurement transducers and systems upon 
initial installation and after major maintenance. Use good engineering 
judgment to repeat the calibration. Follow the torque transducer 
manufacturer's instructions for linearizing your torque sensor's output. 
We recommend that you calibrate the torque-measurement system with a 
reference force and a lever arm.
    (b) Recommended procedure to quantify lever-arm length. Quantify the 
lever-arm length, NIST-traceable within [0.5% uncertainty. The lever 
arm's length must be measured from the centerline of the dynamometer to 
the point at which the reference force is measured. The lever arm must 
be perpendicular to gravity (i.e., horizontal), and it must be 
perpendicular to the dynamometer's rotational axis. Balance the lever 
arm's torque or quantify its net hanging torque, NIST-traceable within 
[1% uncertainty, and account for it as part of the reference torque.
    (c) Recommended procedure to quantify reference force. We recommend 
dead-weight calibration, but you may use either of the following 
procedures to quantify the reference force, NIST-traceable within [0.5% 
uncertainty.
    (1) Dead-weight calibration. This technique applies a known force by 
hanging known weights at a known distance along a lever arm. Make sure 
the weights' lever arm is perpendicular to gravity (i.e., horizontal) 
and perpendicular to the dynamometer's rotational axis. Apply at least 
six calibration-weight combinations for each applicable torque-measuring 
range, spacing the weight quantities about equally over the range. 
Oscillate or rotate the dynamometer during calibration to reduce 
frictional static hysteresis. Determine each weight's reference force by 
multiplying its NIST-traceable mass by the local acceleration of Earth's 
gravity, as described in Sec. 1065.630. Calculate the reference torque 
as the weights' reference force multiplied by the lever arm reference 
length.
    (2) Strain gage, load transducer, or proving ring calibration. This 
technique applies force either by hanging weights on a lever arm (these 
weights and their lever arm length are not used as part of the reference 
torque determination) or by operating the dynamometer at different 
torques. Apply at least six force combinations for each applicable 
torque-measuring range, spacing the force quantities about equally over 
the range. Oscillate or rotate the dynamometer during calibration to 
reduce frictional static hysteresis. In this case, the reference torque 
is determined by multiplying the force output from the reference meter 
(such as a strain gage, load transducer, or proving ring) by its 
effective lever-arm length, which you measure from the point where the 
force measurement is made to the dynamometer's rotational axis. Make 
sure you measure this length perpendicular to the reference meter's 
measurement axis and perpendicular to the dynamometer's rotational axis.

[79 FR 23768, Apr. 28, 2014]



Sec. 1065.315  Pressure, temperature, and dewpoint calibration.

    (a) Calibrate instruments for measuring pressure, temperature, and 
dewpoint upon initial installation. Follow the instrument manufacturer's 
instructions and use good engineering judgment to repeat the 
calibration, as follows:
    (1) Pressure. We recommend temperature-compensated, digital-
pneumatic, or deadweight pressure calibrators, with data-logging 
capabilities to minimize transcription errors. We recommend using 
calibration reference quantities that are NIST-traceable within 0.5% 
uncertainty.

[[Page 111]]

    (2) Temperature. We recommend digital dry-block or stirred-liquid 
temperature calibrators, with data logging capabilities to minimize 
transcription errors. We recommend using calibration reference 
quantities that are NIST-traceable within 0.5% uncertainty. You may 
perform linearity verification for temperature measurement systems with 
thermocouples, RTDs, and thermistors by removing the sensor from the 
system and using a simulator in its place. Use a NIST-traceable 
simulator that is independently calibrated and, as appropriate, cold-
junction compensated. The simulator uncertainty scaled to absolute 
temperature must be less than 0.5% of Tmax. If you use this 
option, you must use sensors that the supplier states are accurate to 
better than 0.5% of Tmax compared with their standard 
calibration curve.
    (3) Dewpoint. We recommend a minimum of three different temperature-
equilibrated and temperature-monitored calibration salt solutions in 
containers that seal completely around the dewpoint sensor. We recommend 
using calibration reference quantities that are NIST-traceable within 
0.5% uncertainty.
    (b) You may remove system components for off-site calibration. We 
recommend specifying calibration reference quantities that are NIST-
traceable within 0.5% uncertainty.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37305, June 30, 2008; 
75 FR 23040, Apr. 30, 2010; 79 FR 23768, Apr. 28, 2014]

                        Flow-Related Measurements



Sec. 1065.320  Fuel-flow calibration.

    (a) Calibrate fuel-flow meters upon initial installation. Follow the 
instrument manufacturer's instructions and use good engineering judgment 
to repeat the calibration.
    (b) You may also develop a procedure based on a chemical balance of 
carbon or oxygen in engine exhaust.
    (c) You may remove system components for off-site calibration. When 
installing a flow meter with an off-site calibration, we recommend that 
you consider the effects of the tubing configuration upstream and 
downstream of the flow meter. We recommend specifying calibration 
reference quantities that are NIST-traceable within 0.5% uncertainty.



Sec. 1065.325  Intake-flow calibration.

    (a) Calibrate intake-air flow meters upon initial installation. 
Follow the instrument manufacturer's instructions and use good 
engineering judgment to repeat the calibration. We recommend using a 
calibration subsonic venturi, ultrasonic flow meter or laminar flow 
element. We recommend using calibration reference quantities that are 
NIST-traceable within 0.5% uncertainty.
    (b) You may remove system components for off-site calibration. When 
installing a flow meter with an off-site calibration, we recommend that 
you consider the effects of the tubing configuration upstream and 
downstream of the flow meter. We recommend specifying calibration 
reference quantities that are NIST-traceable within 0.5% uncertainty.
    (c) If you use a subsonic venturi or ultrasonic flow meter for 
intake flow measurement, we recommend that you calibrate it as described 
in Sec. 1065.340.



Sec. 1065.330  Exhaust-flow calibration.

    (a) Calibrate exhaust-flow meters upon initial installation. Follow 
the instrument manufacturer's instructions and use good engineering 
judgment to repeat the calibration. We recommend that you use a 
calibration subsonic venturi or ultrasonic flow meter and simulate 
exhaust temperatures by incorporating a heat exchanger between the 
calibration meter and the exhaust-flow meter. If you can demonstrate 
that the flow meter to be calibrated is insensitive to exhaust 
temperatures, you may use other reference meters such as laminar flow 
elements, which are not commonly designed to withstand typical raw 
exhaust temperatures. We recommend using calibration reference 
quantities that are NIST-traceable within 0.5% uncertainty.
    (b) You may remove system components for off-site calibration. When 
installing a flow meter with an off-site calibration, we recommend that 
you consider the effects of the tubing configuration upstream and 
downstream of

[[Page 112]]

the flow meter. We recommend specifying calibration reference quantities 
that are NIST-traceable within 0.5% uncertainty.
    (c) If you use a subsonic venturi or ultrasonic flow meter for raw 
exhaust flow measurement, we recommend that you calibrate it as 
described in Sec. 1065.340.



Sec. 1065.340  Diluted exhaust flow (CVS) calibration.

    (a) Overview. This section describes how to calibrate flow meters 
for diluted exhaust constant-volume sampling (CVS) systems.
    (b) Scope and frequency. Perform this calibration while the flow 
meter is installed in its permanent position, except as allowed in 
paragraph (c) of this section. Perform this calibration after you change 
any part of the flow configuration upstream or downstream of the flow 
meter that may affect the flow-meter calibration. Perform this 
calibration upon initial CVS installation and whenever corrective action 
does not resolve a failure to meet the diluted exhaust flow verification 
(i.e., propane check) in Sec. 1065.341.
    (c) Ex-situ CFV and SSV calibration. You may remove a CFV or SSV 
from its permanent position for calibration as long as it meets the 
following requirements when installed in the CVS:
    (1) Upon installation of the CFV or SSV into the CVS, use good 
engineering judgment to verify that you have not introduced any leaks 
between the CVS inlet and the venturi.
    (2) After ex-situ venturi calibration, you must verify all venturi 
flow combinations for CFVs or at minimum of 10 flow points for an SSV 
using the propane check as described in Sec. 1065.341. Your propane 
check result for each venturi flow point may not exceed the tolerance in 
Sec. 1065.341(f)(5).
    (3) To verify your ex-situ calibration for a CVS with more than a 
single CFV, perform the following check to verify that there are no flow 
meter entrance effects that can prevent you from passing this 
verification.
    (i) Use a constant flow device like a CFO kit to deliver a constant 
flow of propane to the dilution tunnel.
    (ii) Measure hydrocarbon concentrations at a minimum of 10 separate 
flow rates for an SSV flow meter, or at all possible flow combinations 
for a CFV flow meter, while keeping the flow of propane constant. We 
recommend selecting CVS flow rates in a random order.
    (iii) Measure the concentration of hydrocarbon background in the 
dilution air at the beginning and end of this test. Subtract the average 
background concentration from each measurement at each flow point before 
performing the regression analysis in paragraph (c)(3)(iv) of this 
section.
    (iv) Perform a power regression using all the paired values of flow 
rate and corrected concentration to obtain a relationship in the form of 
y = a [middot] x \b\. Use concentration as the independent variable and 
flow rate as the dependent variable. For each data point, calculate the 
difference between the measured flow rate and the value represented by 
the curve fit. The difference at each point must be less than [1% of the 
appropriate regression value. The value of b must be between -1.005 and 
-0.995. If your results do not meet these limits, take corrective action 
consistent with Sec. 1065.341(a).
    (d) Reference flow meter. Calibrate a CVS flow meter using a 
reference flow meter such as a subsonic venturi flow meter, a long-
radius ASME/NIST flow nozzle, a smooth approach orifice, a laminar flow 
element, a set of critical flow venturis, or an ultrasonic flow meter. 
Use a reference flow meter that reports quantities that are NIST-
traceable within [1% uncertainty. Use this reference flow meter's 
response to flow as the reference value for CVS flow-meter calibration.
    (e) Configuration. Calibrate the system with any upstream screens or 
other restrictions that will be used during testing and that could 
affect the flow ahead of the CVS flow meter, using good engineering 
judgment to minimize the effect on the flow distribution. You may not 
use any upstream screen or other restriction that could affect the flow 
ahead of the reference flow meter, unless the flow meter has been 
calibrated with such a restriction. In the case of a free standing SSV 
reference flow meter, you may not have any upstream screens.

[[Page 113]]

    (f) PDP calibration. Calibrate a positive-displacement pump (PDP) to 
determine a flow-versus-PDP speed equation that accounts for flow 
leakage across sealing surfaces in the PDP as a function of PDP inlet 
pressure. Determine unique equation coefficients for each speed at which 
you operate the PDP. Calibrate a PDP flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Leaks between the calibration flow meter and the PDP must be 
less than 0.3% of the total flow at the lowest calibrated flow point; 
for example, at the highest restriction and lowest PDP-speed point.
    (3) While the PDP operates, maintain a constant temperature at the 
PDP inlet within [2% of the mean absolute inlet temperature, 
Tin.
    (4) Set the PDP speed to the first speed point at which you intend 
to calibrate.
    (5) Set the variable restrictor to its wide-open position.
    (6) Operate the PDP for at least 3 min to stabilize the system. 
Continue operating the PDP and record the mean values of at least 30 
seconds of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter, 
niref. This may include several measurements of different 
quantities, such as reference meter pressures and temperatures, for 
calculating niref.
    (ii) The mean temperature at the PDP inlet, Tin.
    (iii) The mean static absolute pressure at the PDP inlet, 
pin.
    (iv) The mean static absolute pressure at the PDP outlet, 
pout.
    (v) The mean PDP speed, fnPDP.
    (7) Incrementally close the restrictor valve to decrease the 
absolute pressure at the inlet to the PDP, pin.
    (8) Repeat the steps in paragraphs (e)(6) and (7) of this section to 
record data at a minimum of six restrictor positions ranging from the 
wide open restrictor position to the minimum expected pressure at the 
PDP inlet or the maximum expected differential (outlet minus inlet) 
pressure across the PDP during testing.
    (9) Calibrate the PDP by using the collected data and the equations 
in Sec. 1065.640.
    (10) Repeat the steps in paragraphs (e)(6) through (9) of this 
section for each speed at which you operate the PDP.
    (11) Use the equations in Sec. 1065.642 to determine the PDP flow 
equation for emission testing.
    (12) Verify the calibration by performing a CVS verification (i.e., 
propane check) as described in Sec. 1065.341.
    (13) During emission testing ensure that the PDP is not operated 
either below the lowest inlet pressure point or above the highest 
differential pressure point in the calibration data.
    (g) SSV calibration. Calibrate a subsonic venturi (SSV) to determine 
its calibration coefficient, Cd, for the expected range of 
inlet pressures. Calibrate an SSV flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Verify that any leaks between the calibration flow meter and the 
SSV are less than 0.3% of the total flow at the highest restriction.
    (3) Start the blower downstream of the SSV.
    (4) While the SSV operates, maintain a constant temperature at the 
SSV inlet within [2% of the mean absolute inlet temperature, 
Tin.
    (5) Set the variable restrictor or variable-speed blower to a flow 
rate greater than the greatest flow rate expected during testing. You 
may not extrapolate flow rates beyond calibrated values, so we recommend 
that you make sure the Reynolds number, Re#, at the SSV 
throat at the greatest calibrated flow rate is greater than the maximum 
Re# expected during testing.
    (6) Operate the SSV for at least 3 min to stabilize the system. 
Continue operating the SSV and record the mean of at least 30 seconds of 
sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter niref. 
This may include several measurements of different quantities for 
calculating niref, such as reference meter pressures and 
temperatures.
    (ii) Optionally, the mean dewpoint of the calibration 
air,Tdew. See Sec. 1065.640 for permissible assumptions.

[[Page 114]]

    (iii) The mean temperature at the venturi inlet,Tin.
    (iv) The mean static absolute pressure at the venturi inlet, 
Pin.
    (v) The mean static differential pressure between the static 
pressure at the venturi inlet and the static pressure at the venturi 
throat, DPSSV.
    (7) Incrementally close the restrictor valve or decrease the blower 
speed to decrease the flow rate.
    (8) Repeat the steps in paragraphs (g)(6) and (7) of this section to 
record data at a minimum of ten flow rates.
    (9) Determine an equation to quantify Cd as a function of 
Re# by using the collected data and the equations in Sec. 
1065.640. Section 1065.640 also includes statistical criteria for 
validating the Cd versus Re# equation.
    (10) Verify the calibration by performing a CVS verification (i.e., 
propane check) as described in Sec. 1065.341 using the new 
Cd versus Re# equation.
    (11) Use the SSV only between the minimum and maximum calibrated 
Re#. If you want to use the SSV at a lower or higher 
Re#, you must recalibrate the SSV.
    (12) Use the equations in Sec. 1065.642 to determine SSV flow 
during a test.
    (h) CFV calibration. Calibrate a critical-flow venturi (CFV) to 
verify its discharge coefficient, Cd, up to the highest 
expected pressure ratio, r, according to Sec. 1065.640. Calibrate a CFV 
flow meter as follows:
    (1) Connect the system as shown in Figure 1 of this section.
    (2) Verify that any leaks between the calibration flow meter and the 
CFV are less than 0.3% of the total flow at the highest restriction.
    (3) Start the blower downstream of the CFV.
    (4) While the CFV operates, maintain a constant temperature at the 
CFV inlet within [2% of the mean absolute inlet temperature, 
Tin.
    (5) Set the variable restrictor to its wide-open position. Instead 
of a variable restrictor, you may alternately vary the pressure 
downstream of the CFV by varying blower speed or by introducing a 
controlled leak. Note that some blowers have limitations on nonloaded 
conditions.
    (6) Operate the CFV for at least 3 min to stabilize the system. 
Continue operating the CFV and record the mean values of at least 30 
seconds of sampled data of each of the following quantities:
    (i) The mean flow rate of the reference flow meter, 
niref. This may include several measurements of different 
quantities, such as reference meter pressures and temperatures, for 
calculating niref.
    (ii) The mean dewpoint of the calibration air,Tdew. See 
Sec. 1065.640 for permissible assumptions during emission measurements.
    (iii) The mean temperature at the venturi inlet,Tin.
    (iv) The mean static absolute pressure at the venturi inlet, 
Pin.
    (v) The mean static differential pressure between the CFV inlet and 
the CFV outlet, DPCFV.
    (7) Incrementally close the restrictor valve or decrease the 
downstream pressure to decrease the differential pressure across the 
CFV, DpCFV.
    (8) Repeat the steps in paragraphs (f)(6) and (7) of this section to 
record mean data at a minimum of ten restrictor positions, such that you 
test the fullest practical range of DPCFV expected during 
testing. We do not require that you remove calibration components or CVS 
components to calibrate at the lowest possible restrictions.
    (9) Determine Cd and the highest allowable pressure 
ratio, r, according to Sec. 1065.640.
    (10) Use Cd to determine CFV flow during an emission 
test. Do not use the CFV above the highest allowed r, as determined in 
Sec. 1065.640.
    (11) Verify the calibration by performing a CVS verification (i.e., 
propane check) as described in Sec. 1065.341.
    (12) If your CVS is configured to operate more than one CFV at a 
time in parallel, calibrate your CVS by one of the following:
    (i) Calibrate every combination of CFVs according to this section 
and Sec. 1065.640. Refer to Sec. 1065.642 for instructions on 
calculating flow rates for this option.
    (ii) Calibrate each CFV according to this section and Sec. 
1065.640. Refer to Sec. 1065.642 for instructions on calculating flow 
rates for this option.

[[Page 115]]

    (i) Ultrasonic flow meter calibration. [Reserved]
    [GRAPHIC] [TIFF OMITTED] TR25OC16.159
    

[[Page 116]]



[70 FR 40516, July 13, 2005, as amended at 73 FR 37305, June 30, 2008; 
75 FR 68463, Nov. 8, 2010; 76 FR 57445, Sept. 15, 2011; 81 FR 74165, 
Oct. 25, 2016]



Sec. 1065.341  CVS, PFD, and batch sampler verification (propane check).

    (a) A propane check serves as a CVS verification to determine if 
there is a discrepancy in measured values of diluted exhaust flow. You 
may use the same procedure to verify PFDs and batch samplers. For 
purposes of PFD and batch sampler verification, read the term CVS to 
mean PFD or batch sampler as appropriate. A propane check also serves as 
a batch-sampler verification to determine if there is a discrepancy in a 
batch sampling system that extracts a sample from a CVS, as described in 
paragraph (g) of this section. Using good engineering judgment and safe 
practices, this check may be performed using a gas other than propane, 
such as CO2 or CO. A failed propane check might indicate one 
or more problems that may require corrective action, as follows:
    (1) Incorrect analyzer calibration. Re-calibrate, repair, or replace 
the FID analyzer.
    (2) Leaks. Inspect CVS tunnel, connections, fasteners, and HC 
sampling system, and repair or replace components.
    (3) Poor mixing. Perform the verification as described in this 
section while traversing a sampling probe across the tunnel's diameter, 
vertically and horizontally. If the analyzer response indicates any 
deviation exceeding [2% of the mean measured concentration, consider 
operating the CVS at a higher flow rate or installing a mixing plate or 
orifice to improve mixing.
    (4) Hydrocarbon contamination in the sample system. Perform the 
hydrocarbon-contamination verification as described in Sec. 1065.520.
    (5) Change in CVS calibration. Perform a calibration of the CVS flow 
meter as described in Sec. 1065.340.
    (6) Flow meter entrance effects. Inspect the CVS tunnel to determine 
whether the entrance effects from the piping configuration upstream of 
the flow meter adversely affect the flow measurement.
    (7) Other problems with the CVS or sampling verification hardware or 
software. Inspect the CVS system, CVS verification hardware, and 
software for discrepancies.
    (b) A propane check uses either a reference mass or a reference flow 
rate of C3H8 as a tracer gas in a CVS. Note that 
if you use a reference flow rate, account for any non-ideal gas behavior 
of C3H8 in the reference flow meter. Refer to 
Sec. 1065.640 and Sec. 1065.642, which describe how to calibrate and 
use certain flow meters. Do not use any ideal gas assumptions in Sec. 
1065.640 and Sec. 1065.642. The propane check compares the calculated 
mass of injected C3H8 using HC measurements and 
CVS flow rate measurements with the reference value.
    (c) Prepare for the propane check as follows:
    (1) If you use a reference mass of C3H8 
instead of a reference flow rate, obtain a cylinder charged with 
C3H8. Determine the reference cylinder's mass of 
C3H8 within [0.5% of the amount of 
C3H8 that you expect to use.
    (2) Select appropriate flow rates for the CVS and 
C3H8.
    (3) Select a C3H8 injection port in the CVS. 
Select the port location to be as close as practical to the location 
where you introduce engine exhaust into the CVS, or at some point in the 
laboratory exhaust tubing upstream of this location. Connect the 
C3H8 cylinder to the injection system.
    (4) Operate and stabilize the CVS.
    (5) Preheat or precool any heat exchangers in the sampling system.
    (6) Allow heated and cooled components such as sample lines, 
filters, chillers, and pumps to stabilize at operating temperature.
    (7) You may purge the HC sampling system during stabilization.
    (8) If applicable, perform a vacuum side leak verification of the HC 
sampling system as described in Sec. 1065.345.
    (9) You may also conduct any other calibrations or verifications on 
equipment or analyzers.
    (d) If you performed the vacuum-side leak verification of the HC 
sampling system as described in paragraph (c)(8) of this section, you 
may use the HC contamination procedure in Sec. 1065.520(f) to verify HC 
contamination. Otherwise,

[[Page 117]]

zero, span, and verify contamination of the HC sampling system, as 
follows:
    (1) Select the lowest HC analyzer range that can measure the 
C3H8 concentration expected for the CVS and 
C3H8 flow rates.
    (2) Zero the HC analyzer using zero air introduced at the analyzer 
port.
    (3) Span the HC analyzer using C3H8 span gas 
introduced at the analyzer port.
    (4) Overflow zero air at the HC probe inlet or into a tee near the 
outlet of the probe.
    (5) Measure the stable HC concentration of the HC sampling system as 
overflow zero air flows. For batch HC measurement, fill the batch 
container (such as a bag) and measure the HC overflow concentration.
    (6) If the overflow HC concentration exceeds 2 [micro] mol/mol, do 
not proceed until contamination is eliminated. Determine the source of 
the contamination and take corrective action, such as cleaning the 
system or replacing contaminated portions.
    (7) When the overflow HC concentration does not exceed 2 [micro] 
mol/mol, record this value as xTHCinit and use it to correct 
for HC contamination as described in Sec. 1065.660.
    (e) Perform the propane check as follows:
    (1) For batch HC sampling, connect clean storage media, such as 
evacuated bags.
    (2) Operate HC measurement instruments according to the instrument 
manufacturer's instructions.
    (3) If you will correct for dilution air background concentrations 
of HC, measure and record background HC in the dilution air.
    (4) Zero any integrating devices.
    (5) Begin sampling, and start any flow integrators.
    (6) Release the contents of the C3H8 reference 
cylinder at the rate you selected. If you use a reference flow rate of 
C3H8, start integrating this flow rate.
    (7) Continue to release the cylinder's contents until at least 
enough C3H8 has been released to ensure accurate 
quantification of the reference C3H8 and the 
measured C3H8.
    (8) Shut off the C3H8 reference cylinder and 
continue sampling until you have accounted for time delays due to sample 
transport and analyzer response.
    (9) Stop sampling and stop any integrators.
    (f) Perform post-test procedure as follows:
    (1) If you used batch sampling, analyze batch samples as soon as 
practical.
    (2) After analyzing HC, correct for contamination and background.
    (3) Calculate total C3H8 mass based on your 
CVS and HC data as described in Sec. 1065.650 (40 CFR 1066.605 for 
vehicle testing) and Sec. 1065.660, using the molar mass of 
C3H8, MC3H8, instead the effective 
molar mass of HC, MHC.
    (4) If you use a reference mass, determine the cylinder's propane 
mass within [0.5% and determine the C3H8 reference 
mass by subtracting the empty cylinder propane mass from the full 
cylinder propane mass.
    (5) Subtract the reference C3H8 mass from the 
calculated mass. If this difference is within [2% of the reference mass, 
the CVS passes this verification. If not, take corrective action as 
described in paragraph (a) of this section.
    (g) You may repeat the propane check to verify a batch sampler, such 
as a PM secondary dilution system. (1) Configure the HC sampling system 
to extract a sample near the location of the batch sampler's storage 
media (such as a PM filter). If the absolute pressure at this location 
is too low to extract an HC sample, you may sample HC from the batch 
sampler pump's exhaust. Use caution when sampling from pump exhaust 
because an otherwise acceptable pump leak downstream of a batch sampler 
flow meter will cause a false failure of the propane check.
    (2) Repeat the propane check described in this section, but sample 
HC from the batch sampler.
    (3) Calculate C3H8 mass, taking into account 
any secondary dilution from the batch sampler.
    (4) Subtract the reference C3H8 mass from the 
calculated mass. If this difference is within [5% of the reference mass, 
the batch sampler passes this

[[Page 118]]

verification. If not, take corrective action as described in paragraph 
(a) of this section.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37307, June 30, 2008; 
73 FR 59328, Oct. 8, 2008; 76 FR 57447, Sept. 15, 2011; 79 FR 23768, 
Apr. 28, 2014; 81 FR 74167, Oct. 25, 2016]



Sec. 1065.342  Sample dryer verification.

    (a) Scope and frequency. If you use a sample dryer as allowed in 
Sec. 1065.145(e)(2) to remove water from the sample gas, verify the 
performance upon installation, after major maintenance, for thermal 
chiller. For osmotic membrane dryers, verify the performance upon 
installation, after major maintenance, and within 35 days of testing.
    (b) Measurement principles. Water can inhibit an analyzer's ability 
to properly measure the exhaust component of interest and thus is 
sometimes removed before the sample gas reaches the analyzer. For 
example water can negatively interfere with a CLD's NOX 
response through collisional quenching and can positively interfere with 
an NDIR analyzer by causing a response similar to CO.
    (c) System requirements. The sample dryer must meet the 
specifications as determined in Sec. 1065.145(e)(2) for dewpoint, 
Tdew, and absolute pressure, ptotal, downstream of 
the osmotic-membrane dryer or thermal chiller.
    (d) Sample dryer verification procedure. Use the following method to 
determine sample dryer performance. Run this verification with the dryer 
and associated sampling system operating in the same manner you will use 
for emission testing (including operation of sample pumps). You may run 
this verification test on multiple sample dryers sharing the same 
sampling system at the same time. You may run this verification on the 
sample dryer alone, but you must use the maximum gas flow rate expected 
during testing. You may use good engineering judgment to develop a 
different protocol.
    (1) Use PTFE or stainless steel tubing to make necessary 
connections.
    (2) Humidify room air, N2, or purified air by bubbling it 
through distilled water in a sealed vessel that humidifies the gas to 
the highest sample water content that you estimate during emission 
sampling.
    (3) Introduce the humidified gas upstream of the sample dryer. You 
may disconnect the transfer line from the probe and introduce the 
humidified gas at the inlet of the transfer line of the sample system 
used during testing. You may use the sample pumps in the sample system 
to draw gas through the vessel.
    (4) Maintain the sample lines, fittings, and valves from the 
location where the humidified gas water content is measured to the inlet 
of the sampling system at a temperature at least 5  deg.C above the 
local humidified gas dewpoint. For dryers used in NOX sample 
systems, verify the sample system components used in this verification 
prevent aqueous condensation as required in Sec. 1065.145(d)(1)(i). We 
recommend that the sample system components be maintained at least 5 
deg.C above the local humidified gas dewpoint to prevent aqueous 
condensation.
    (5) Measure the humidified gas dewpoint, Tdew, and 
absolute pressure, ptotal, as close as possible to the inlet 
of the sample dryer or inlet of the sample system to verify the water 
content is at least as high as the highest value that you estimated 
during emission sampling. You may verify the water content based on any 
humidity parameter (e.g. mole fraction water, local dewpoint, or 
absolute humidity).
    (6) Measure the humidified gas dewpoint, Tdew, and 
absolute pressure, ptotal, as close as possible to the outlet 
of the sample dryer. Note that the dewpoint changes with absolute 
pressure. If the dewpoint at the sample dryer outlet is measured at a 
different pressure, then this reading must be corrected to the dewpoint 
at the sample dryer absolute pressure, ptotal.
    (7) The sample dryer meets the verification if the dewpoint at the 
sample dryer pressure as measured in paragraph (d)(6) of this section is 
less than the dewpoint corresponding to the sample dryer specifications 
as determined in Sec. 1065.145(e)(2) plus 2  deg.C or if the mole 
fraction of water as measured in (d)(6) is less than the corresponding 
sample dryer specifications plus 0.002 mol/mol.
    (e) Alternate sample dryer verification procedure. The following 
method may

[[Page 119]]

be used in place of the sample dryer verification procedure in (d) of 
this section. If you use a humidity sensor for continuous monitoring of 
dewpoint at the sample dryer outlet you may skip the performance check 
in Sec. 1065.342(d), but you must make sure that the dryer outlet 
humidity is at or below the minimum value used for quench, interference, 
and compensation checks.

[73 FR 37307, June 30, 2008, as amended at 73 FR 59328, Oct. 8, 2008; 75 
FR 23040, Apr. 30, 2010]



Sec. 1065.345  Vacuum-side leak verification.

    (a) Scope and frequency. Verify that there are no significant 
vacuum-side leaks using one of the leak tests described in this section. 
For laboratory testing, perform the vacuum-side leak verification upon 
initial sampling system installation, within 8 hours before the start of 
the first test interval of each duty-cycle sequence, and after 
maintenance such as pre-filter changes. For field testing, perform the 
vacuum-side leak verification after each installation of the sampling 
system on the vehicle, prior to the start of the field test, and after 
maintenance such as pre-filter changes. This verification does not apply 
to any full-flow portion of a CVS dilution system.
    (b) Measurement principles. A leak may be detected either by 
measuring a small amount of flow when there should be zero flow, or by 
detecting the dilution of a known concentration of span gas when it 
flows through the vacuum side of a sampling system.
    (c) Low-flow leak test. Test a sampling system for low-flow leaks as 
follows:
    (1) Seal the probe end of the system by taking one of the following 
steps:
    (i) Cap or plug the end of the sample probe.
    (ii) Disconnect the transfer line at the probe and cap or plug the 
transfer line.
    (iii) Close a leak-tight valve located in the sample transfer line 
within 92 cm of the probe.
    (2) Operate all vacuum pumps. After stabilizing, verify that the 
flow through the vacuum-side of the sampling system is less than 0.5% of 
the system's normal in-use flow rate. You may estimate typical analyzer 
and bypass flows as an approximation of the system's normal in-use flow 
rate.
    (d) Dilution-of-span-gas leak test. You may use any gas analyzer for 
this test. If you use a FID for this test, correct for any HC 
contamination in the sampling system according to Sec. 1065.660. To 
avoid misleading results from this test, we recommend using only 
analyzers that have a repeatability of 0.5% or better at the span gas 
concentration used for this test. Perform a vacuum-side leak test as 
follows:
    (1) Prepare a gas analyzer as you would for emission testing.
    (2) Supply span gas to the analyzer span port and record the 
measured value.
    (3) Route overflow span gas to the inlet of the sample probe or at a 
tee fitting in the transfer line near the exit of the probe. You may use 
a valve upstream of the overflow fitting to prevent overflow of span gas 
out of the inlet of the probe, but you must then provide an overflow 
vent in the overflow supply line.
    (4) Verify that the measured overflow span gas concentration is 
within [0.5% of the concentration measured in paragraph (d)(2) of this 
section. A measured value lower than expected indicates a leak, but a 
value higher than expected may indicate a problem with the span gas or 
the analyzer itself. A measured value higher than expected does not 
indicate a leak.
    (e) Vacuum-decay leak test. To perform this test you must apply a 
vacuum to the vacuum-side volume of your sampling system and then 
observe the leak rate of your system as a decay in the applied vacuum. 
To perform this test you must know the vacuum-side volume of your 
sampling system to within [10% of its true volume. For this test you 
must also use measurement instruments that meet the specifications of 
subpart C of this part and of this subpart D. Perform a vacuum-decay 
leak test as follows:
    (1) Seal the probe end of the system as close to the probe opening 
as possible by taking one of the following steps:
    (i) Cap or plug the end of the sample probe.

[[Page 120]]

    (ii) Disconnect the transfer line at the probe and cap or plug the 
transfer line.
    (iii) Close a leak-tight valve located in the sample transfer line 
within 92 cm of the probe.
    (2) Operate all vacuum pumps. Draw a vacuum that is representative 
of normal operating conditions. In the case of sample bags, we recommend 
that you repeat your normal sample bag pump-down procedure twice to 
minimize any trapped volumes.
    (3) Turn off the sample pumps and seal the system. Measure and 
record the absolute pressure of the trapped gas and optionally the 
system absolute temperature. Wait long enough for any transients to 
settle and long enough for a leak at 0.5% to have caused a pressure 
change of at least 10 times the resolution of the pressure transducer, 
then again record the pressure and optionally temperature.
    (4) Calculate the leak flow rate based on an assumed value of zero 
for pumped-down bag volumes and based on known values for the sample 
system volume, the initial and final pressures, optional temperatures, 
and elapsed time. Using the calculations specified in Sec. 1065.644, 
verify that the vacuum-decay leak flow rate is less than 0.5% of the 
system's normal in-use flow rate.

[73 FR 37307, June 30, 2008, as amended at 73 FR 59328, Oct. 8, 2008; 75 
FR 23040, Apr. 30, 2010; 81 FR 74167, Oct. 25, 2016]

                   CO and CO2 Measurements



Sec. 1065.350  H[bdi2] O interference verification for CO[bdi2] NDIR
analyzers.

    (a) Scope and frequency. If you measure CO2 using an NDIR 
analyzer, verify the amount of H2O interference after initial 
analyzer installation and after major maintenance.
    (b) Measurement principles. H2O can interfere with an 
NDIR analyzer's response to CO2.
    If the NDIR analyzer uses compensation algorithms that utilize 
measurements of other gases to meet this interference verification, 
simultaneously conduct these other measurements to test the compensation 
algorithms during the analyzer interference verification.
    (c) System requirements. A CO2 NDIR analyzer must have an 
H2O interference that is within (0.0 [0.4) mmol/mol, though 
we strongly recommend a lower interference that is within (0.0 [0.2) 
mmol/mol.
    (d) Procedure. Perform the interference verification as follows:
    (1) Start, operate, zero, and span the CO2 NDIR analyzer 
as you would before an emission test. If the sample is passed through a 
dryer during emission testing, you may run this verification test with 
the dryer if it meets the requirements of Sec. 1065.342. Operate the 
dryer at the same conditions as you will for an emission test. You may 
also run this verification test without the sample dryer.
    (2) Create a humidified test gas by bubbling zero gas that meets the 
specifications in Sec. 1065.750 through distilled H2O in a 
sealed vessel. If the sample is not passed through a dryer during 
emission testing, control the vessel temperature to generate an 
H2O level at least as high as the maximum expected during 
emission testing. If the sample is passed through a dryer during 
emission testing, control the vessel temperature to generate an 
H2O level at least as high as the level determined in Sec. 
1065.145(e)(2) for that dryer.
    (3) Introduce the humidified test gas into the sample system. You 
may introduce it downstream of any sample dryer, if one is used during 
testing.
    (4) If the sample is not passed through a dryer during this 
verification test, measure the H2O mole fraction, 
xH2O, of the humidified test gas, as close as possible to the 
inlet of the analyzer. For example, measure dewpoint, Tdew, 
and absolute pressure, ptotal, to calculate xH2O. 
Verify that the H2O content meets the requirement in 
paragraph (d)(2) of this section. If the sample is passed through a 
dryer during this verification test, you must verify that the 
H2O content of the humidified test gas downstream of the 
vessel meets the requirement in paragraph (d)(2) of this section based 
on either direct measurement of the H2O content (e.g., 
dewpoint and pressure) or

[[Page 121]]

an estimate based on the vessel pressure and temperature. Use good 
engineering judgment to estimate the H2O content. For 
example, you may use previous direct measurements of H2O 
content to verify the vessel's level of saturation.
    (5) If a sample dryer is not used in this verification test, use 
good engineering judgment to prevent condensation in the transfer lines, 
fittings, or valves from the point where xH2O is measured to 
the analyzer. We recommend that you design your system so the wall 
temperatures in the transfer lines, fittings, and valves from the point 
where xH2O is measured to the analyzer are at least 5  deg.C 
above the local sample gas dewpoint.
    (6) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the transfer line and to account for 
analyzer response.
    (7) While the analyzer measures the sample's concentration, record 
30 seconds of sampled data. Calculate the arithmetic mean of this data. 
The analyzer meets the interference verification if this value is within 
(0.0 [0.4) mmol/mol.
    (e) Exceptions. The following exceptions apply:
    (1) You may omit this verification if you can show by engineering 
analysis that for your CO2 sampling system and your emission-
calculation procedures, the H2O interference for your 
CO2 NDIR analyzer always affects your brake-specific emission 
results within [0.5% of each of the applicable standards. This 
specification also applies for vehicle testing, except that it relates 
to emission results in g/mile or g/kilometer.
    (2) You may use a CO2 NDIR analyzer that you determine 
does not meet this verification, as long as you try to correct the 
problem and the measurement deficiency does not adversely affect your 
ability to show that engines comply with all applicable emission 
standards.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37308, June 30, 2008; 
73 FR 59328, Oct. 8, 2008; 75 FR 23040, Apr. 30, 2010; 76 FR 57447, 
Sept. 15, 2011; 79 FR 23768, Apr. 28, 2014]



Sec. 1065.355  H[bdi2] O and CO[bdi2] interference verification for
CO NDIR analyzers.

    (a) Scope and frequency. If you measure CO using an NDIR analyzer, 
verify the amount of H2O and CO2 interference 
after initial analyzer installation and after major maintenance.
    (b) Measurement principles. H2O and CO2 can 
positively interfere with an NDIR analyzer by causing a response similar 
to CO. If the NDIR analyzer uses compensation algorithms that utilize 
measurements of other gases to meet this interference verification, 
simultaneously conduct these other measurements to test the compensation 
algorithms during the analyzer interference verification.
    (c) System requirements. A CO NDIR analyzer must have combined 
H2O and CO2 interference that is within [2 % of 
the flow-weighted mean concentration of CO expected at the standard, 
though we strongly recommend a lower interference that is within [1%.
    (d) Procedure. Perform the interference verification as follows:
    (1) Start, operate, zero, and span the CO NDIR analyzer as you would 
before an emission test. If the sample is passed through a dryer during 
emission testing, you may run this verification test with the dryer if 
it meets the requirements of Sec. 1065.342. Operate the dryer at the 
same conditions as you will for an emission test. You may also run this 
verification test without the sample dryer.
    (2) Create a humidified CO2 test gas by bubbling a 
CO2 span gas that meets the specifications in Sec. 1065.750 
through distilled H2O in a sealed vessel. If the sample is 
not passed through a dryer during emission testing, control the vessel 
temperature to generate an H2O level at least as high as the 
maximum expected during emission testing. If the sample is passed 
through a dryer during emission testing, control the vessel temperature 
to generate an H2O level at least as high as the level 
determined in Sec. 1065.145(e)(2) for that dryer. Use a CO2 
span gas concentration at least as high as the maximum expected during 
testing.
    (3) Introduce the humidified CO2 test gas into the sample 
system. You may introduce it downstream of any sample dryer, if one is 
used during testing.

[[Page 122]]

    (4) If the sample is not passed through a dryer during this 
verification test, measure the H2O mole fraction, 
xH2O, of the humidified CO2 test gas as close as 
possible to the inlet of the analyzer. For example, measure dewpoint, 
Tdew, and absolute pressure, ptotal, to calculate 
xH2O. Verify that the H2O content meets 
the requirement in paragraph (d)(2) of this section. If the sample is 
passed through a dryer during this verification test, you must verify 
that the H2O content of the humidified test gas downstream of 
the vessel meets the requirement in paragraph (d)(2) of this section 
based on either direct measurement of the H2O content (e.g., 
dewpoint and pressure) or an estimate based on the vessel pressure and 
temperature. Use good engineering judgment to estimate the 
H2O content. For example, you may use previous direct 
measurements of H2O content to verify the vessel's level of 
saturation.
    (5) If a sample dryer is not used in this verification test, use 
good engineering judgment to prevent condensation in the transfer lines, 
fittings, or valves from the point where xH2O is measured to 
the analyzer. We recommend that you design your system so that the wall 
temperatures in the transfer lines, fittings, and valves from the point 
where xH2O is measured to the analyzer are at least 5  deg.C 
above the local sample gas dewpoint.
    (6) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the transfer line and to account for 
analyzer response.
    (7) While the analyzer measures the sample's concentration, record 
its output for 30 seconds. Calculate the arithmetic mean of this data.
    (8) The analyzer meets the interference verification if the result 
of paragraph (d)(7) of this section meets the tolerance in paragraph (c) 
of this section.
    (9) You may also run interference procedures for CO2 and 
H2O separately. If the CO2 and H2O 
levels used are higher than the maximum levels expected during testing, 
you may scale down each observed interference value by multiplying the 
observed interference by the ratio of the maximum expected concentration 
value to the actual value used during this procedure. You may run 
separate interference concentrations of H2O (down to 0.025 
mol/mol H2O content) that are lower than the maximum levels 
expected during testing, but you must scale up the observed 
H2O interference by multiplying the observed interference by 
the ratio of the maximum expected H2O concentration value to 
the actual value used during this procedure. The sum of the two scaled 
interference values must meet the tolerance in paragraph (c) of this 
section.
    (e) Exceptions. The following exceptions apply:
    (1) You may omit this verification if you can show by engineering 
analysis that for your CO sampling system and your emission-calculation 
procedures, the combined CO2 and H2O interference 
for your CO NDIR analyzer always affects your brake-specific CO emission 
results within [0.5% of the applicable CO standard.
    (2) You may use a CO NDIR analyzer that you determine does not meet 
this verification, as long as you try to correct the problem and the 
measurement deficiency does not adversely affect your ability to show 
that engines comply with all applicable emission standards.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37308, June 30, 2008; 
73 FR 59328, Oct. 8, 2008; 75 FR 23041, Apr. 30, 2010; 79 FR 23769, Apr. 
28, 2014]

                        Hydrocarbon Measurements



Sec. 1065.360  FID optimization and verification.

    (a) Scope and frequency. For all FID analyzers, calibrate the FID 
upon initial installation. Repeat the calibration as needed using good 
engineering judgment. For a FID that measures THC, perform the following 
steps:
    (1) Optimize the response to various hydrocarbons after initial 
analyzer installation and after major maintenance as described in 
paragraph (c) of this section.
    (2) Determine the methane (CH4) response factor after 
initial analyzer installation and after major maintenance as described 
in paragraph (d) of this section.

[[Page 123]]

    (3) If you determine NMNEHC by subtracting from measured THC, 
determine the ethane (C2H6) response factor after 
initial analyzer installation and after major maintenance as described 
in paragraph (f) of this section. Verify the C2H6 
response within 185 days before testing as described in paragraph (f) of 
this section.
    (b) Calibration. Use good engineering judgment to develop a 
calibration procedure, such as one based on the FID-analyzer 
manufacturer's instructions and recommended frequency for calibrating 
the FID. Alternately, you may remove system components for off-site 
calibration. For a FID that measures THC, calibrate using 
C3H8 calibration gases that meet the 
specifications of Sec. 1065.750. For a FID that measures 
CH4, calibrate using CH4 calibration gases that 
meet the specifications of Sec. 1065.750. We recommend FID analyzer 
zero and span gases that contain approximately the flow-weighted mean 
concentration of O2 expected during testing. If you use a FID 
to measure CH4 downstream of a nonmethane cutter, you may 
calibrate that FID using CH4 calibration gases with the 
cutter. Regardless of the calibration gas composition, calibrate on a 
carbon number basis of one (C1). For example, if you use a 
C3H8 span gas of concentration 200 [micro] mol/
mol, span the FID to respond with a value of 600 [micro] mol/mol. As 
another example, if you use a CH4 span gas with a 
concentration of 200 [micro] mol/mol, span the FID to respond with a 
value of 200 [micro] mol/mol.
    (c) THC FID response optimization. This procedure is only for FID 
analyzers that measure THC. Use good engineering judgment for initial 
instrument start-up and basic operating adjustment using FID fuel and 
zero air. Heated FIDs must be within their required operating 
temperature ranges. Optimize FID response at the most common analyzer 
range expected during emission testing. Optimization involves adjusting 
flows and pressures of FID fuel, burner air, and sample to minimize 
response variations to various hydrocarbon species in the exhaust. Use 
good engineering judgment to trade off peak FID response to propane 
calibration gases to achieve minimal response variations to different 
hydrocarbon species. For an example of trading off response to propane 
for relative responses to other hydrocarbon species, see SAE 770141 
(incorporated by reference in Sec. 1065.1010). Determine the optimum 
flow rates and/or pressures for FID fuel, burner air, and sample and 
record them for future reference.
    (d) THC FID CH4 response factor determination. This procedure is 
only for FID analyzers that measure THC. Since FID analyzers generally 
have a different response to CH4 versus 
C3H8, determine the THC-FID analyzer's 
CH4 response factor, RFCH4[THC-FID], after FID 
optimization. Use the most recent RFCH4[THC-FID] measured 
according to this section in the calculations for HC determination 
described in Sec. 1065.660 to compensate for CH4 response. 
Determine RFCH4[THC-FID] as follows, noting that you do not 
determine RFCH4[THC-FID] for FIDs that are calibrated and 
spanned using CH4 with a nonmethane cutter:
    (1) Select a C3 H8 span gas concentration that 
you use to span your analyzers before emission testing. Use only span 
gases that meet the specifications of Sec. 1065.750. Record the 
C3H8 concentration of the gas.
    (2) Select a CH4 span gas concentration that you use to 
span your analyzers before emission testing. Use only span gases that 
meet the specifications of Sec. 1065.750. Record the CH4 
concentration of the gas.
    (3) Start and operate the FID analyzer according to the 
manufacturer's instructions.
    (4) Confirm that the FID analyzer has been calibrated using 
C3H8. Calibrate on a carbon number basis of one 
(C1). For example, if you use a C3 H8 
span gas of concentration 200 [micro] mol/mol, span the FID to respond 
with a value of 600 [micro] mol/mol.
    (5) Zero the FID with a zero gas that you use for emission testing.
    (6) Span the FID with the C3H8 span gas that 
you selected under paragraph (d)(1) of this section.
    (7) Introduce the CH4 span gas that you selected under 
paragraph (d)(2) of this section into the FID analyzer.
    (8) Allow time for the analyzer response to stabilize. Stabilization 
time

[[Page 124]]

may include time to purge the analyzer and to account for its response.
    (9) While the analyzer measures the CH4 concentration, 
record 30 seconds of sampled data. Calculate the arithmetic mean of 
these values.
    (10) For analyzers with multiple ranges, you need to perform the 
procedure in this paragraph (d) only on a single range.
    (11) Divide the mean measured concentration by the recorded span 
concentration of the CH4 calibration gas. The result is the 
FID analyzer's response factor for CH4, RF 
CH4[THC-FID].
    (e) THC FID CH4 response verification. This procedure is 
only for FID analyzers that measure THC. Verify 
RFCH4[THC-FID] as follows:
    (1) Perform a CH4 response factor determination as 
described in paragraph (d) of this section. If the resulting value of 
RFCH4[THC-FID] is within [5% of its most recent previously 
determined value, the THC FID passes the CH4 response 
verification. For example, if the most recent previous value for RF 
CH4[THC-FID] was 1.05 and it increased by 0.05 to become 1.10 
or it decreased by 0.05 to become 1.00, either case would be acceptable 
because [4.8% is less than [5%.
    (2) If RF CH4[THC-FID] is not within the tolerance 
specified in paragraph (e)(1) of this section, use good engineering 
judgment to verify that the flow rates and/or pressures of FID fuel, 
burner air, and sample are at their most recent previously recorded 
values, as determined in paragraph (c) of this section. You may adjust 
these flow rates as necessary. Then determine the RF 
CH4[THC-FID] as described in paragraph (d) of this section 
and verify that it is within the tolerance specified in this paragraph 
(e).
    (3) If RF CH4[THC-FID] is not within the tolerance 
specified in this paragraph (e), re-optimize the FID response as 
described in paragraph (c) of this section.
    (4) Determine a new RFCH4[THC-FID] as described in 
paragraph (d) of this section. Use this new value of RF 
CH4[THC-FID] in the calculations for HC determination, as 
described in Sec. 1065.660.
    (5) For analyzers with multiple ranges, you need to perform the 
procedure in this paragraph (e) only on a single range.
    (f) THC FID C2H6 response factor 
determination. This procedure is only for FID analyzers that measure 
THC. Since FID analyzers generally have a different response to 
C2H6 than C3H8, determine 
the THC-FID analyzer's C2H6 response factor, 
RFC2H6[THC-FID], after FID optimization using the procedure 
described in paragraph (d) of this section, replacing CH4 
with C2H6. Use the most recent 
RFC2H6[THC-FID] measured according to this section in the 
calculations for HC determination described in Sec. 1065.660 to 
compensate for C2H6 response.

[73 FR 37308, June 30, 2008, as amended at 75 FR 23041, Apr. 30, 2010; 
76 FR 57447, Sept. 15, 2011; 79 FR 23769, Apr. 28, 2014; 81 FR 74168, 
Oct. 25, 2016]



Sec. 1065.362  Non-stoichiometric raw exhaust FID O[bdi2] interference
verification.

    (a) Scope and frequency. If you use FID analyzers for raw exhaust 
measurements from engines that operate in a non-stoichiometric mode of 
combustion (e.g., compression-ignition, lean-burn), verify the amount of 
FID O2 interference upon initial installation and after major 
maintenance.
    (b) Measurement principles. Changes in O2 concentration 
in raw exhaust can affect FID response by changing FID flame 
temperature. Optimize FID fuel, burner air, and sample flow to meet this 
verification. Verify FID performance with the compensation algorithms 
for FID O2 interference that you have active during an 
emission test.
    (c) System requirements. Any FID analyzer used during testing must 
meet the FID O2 interference verification according to the 
procedure in this section.
    (d) Procedure. Determine FID O2 interference as follows, 
noting that you may use one or more gas dividers to create the reference 
gas concentrations that are required to perform this verification:
    (1) Select three span reference gases that contain a 
C3H8 concentration that you use to span your 
analyzers before emission testing. Use only span gases that meet the 
specifications of

[[Page 125]]

Sec. 1065.750. You may use CH4 span reference gases for FIDs 
calibrated on CH4 with a nonmethane cutter. Select the three 
balance gas concentrations such that the concentrations of O2 
and N2 represent the minimum, maximum, and average 
O2 concentrations expected during testing. The requirement 
for using the average O2 concentration can be removed if you 
choose to calibrate the FID with span gas balanced with the average 
expected oxygen concentration.
    (2) Confirm that the FID analyzer meets all the specifications of 
Sec. 1065.360.
    (3) Start and operate the FID analyzer as you would before an 
emission test. Regardless of the FID burner's air source during testing, 
use zero air as the FID burner's air source for this verification.
    (4) Zero the FID analyzer using the zero gas used during emission 
testing.
    (5) Span the FID analyzer using a span gas that you use during 
emission testing.
    (6) Check the zero response of the FID analyzer using the zero gas 
used during emission testing. If the mean zero response of 30 seconds of 
sampled data is within [0.5% of the span reference value used in 
paragraph (d)(5) of this section, then proceed to the next step; 
otherwise restart the procedure at paragraph (d)(4) of this section.
    (7) Check the analyzer response using the span gas that has the 
minimum concentration of O2 expected during testing. Record 
the mean response of 30 seconds of stabilized sample data as 
xO2minHC.
    (8) Check the zero response of the FID analyzer using the zero gas 
used during emission testing. If the mean zero response of 30 seconds of 
stabilized sample data is within [0.5% of the span reference value used 
in paragraph (d)(5) of this section, then proceed to the next step; 
otherwise restart the procedure at paragraph (d)(4) of this section.
    (9) Check the analyzer response using the span gas that has the 
average concentration of O2 expected during testing. Record 
the mean response of 30 seconds of stabilized sample data as 
xO2avgHC.
    (10) Check the zero response of the FID analyzer using the zero gas 
used during emission testing. If the mean zero response of 30 seconds of 
stabilized sample data is within [0.5% of the span reference value used 
in paragraph (d)(5) of this section, proceed to the next step; otherwise 
restart the procedure at paragraph (d)(4) of this section.
    (11) Check the analyzer response using the span gas that has the 
maximum concentration of O2 expected during testing. Record 
the mean response of 30 seconds of stabilized sample data as 
xO2maxHC.
    (12) Check the zero response of the FID analyzer using the zero gas 
used during emission testing. If the mean zero response of 30 seconds of 
stabilized sample data is within [0.5% of the span reference value used 
in paragraph (d)(5) of this section, then proceed to the next step; 
otherwise restart the procedure at paragraph (d)(4) of this section.
    (13) Calculate the percent difference between xO2maxHC 
and its reference gas concentration. Calculate the percent difference 
between xO2avgHC and its reference gas concentration. 
Calculate the percent difference between xO2minHC and its 
reference gas concentration. Determine the maximum percent difference of 
the three. This is the O2 interference.
    (14) If the O2 interference is within [2%, the FID passes 
the O2 interference verification; otherwise perform one or 
more of the following to address the deficiency:
    (i) Repeat the verification to determine if a mistake was made 
during the procedure.
    (ii) Select zero and span gases for emission testing that contain 
higher or lower O2 concentrations and repeat the 
verification.
    (iii) Adjust FID burner air, fuel, and sample flow rates. Note that 
if you adjust these flow rates on a THC FID to meet the O2 
interference verification, you have reset RFCH4 for the next 
RFCH4 verification according to Sec. 1065.360. Repeat the 
O2 interference verification after adjustment and determine 
RFCH4.
    (iv) Repair or replace the FID and repeat the O2 
interference verification.
    (v) Demonstrate that the deficiency does not adversely affect your 
ability to demonstrate compliance with the applicable emission 
standards.

[[Page 126]]

    (15) For analyzers with multiple ranges, you need to perform the 
procedure in this paragraph (d) only on a single range.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37309, June 30, 2008; 
79 FR 23770, Apr. 28, 2014]



Sec. 1065.365  Nonmethane cutter penetration fractions.

    (a) Scope and frequency. If you use a FID analyzer and a nonmethane 
cutter (NMC) to measure methane (CH4), determine the 
nonmethane cutter's penetration fractions of CH4, 
PFCH4, and ethane, PFC2H6. As detailed in this 
section, these penetration fractions may be determined as a combination 
of NMC penetration fractions and FID analyzer response factors, 
depending on your particular NMC and FID analyzer configuration. Perform 
this verification after installing the nonmethane cutter. Repeat this 
verification within 185 days of testing to verify that the catalytic 
activity of the cutter has not deteriorated. Note that because 
nonmethane cutters can deteriorate rapidly and without warning if they 
are operated outside of certain ranges of gas concentrations and outside 
of certain temperature ranges, good engineering judgment may dictate 
that you determine a nonmethane cutter's penetration fractions more 
frequently.
    (b) Measurement principles. A nonmethane cutter is a heated catalyst 
that removes nonmethane hydrocarbons from an exhaust sample stream 
before the FID analyzer measures the remaining hydrocarbon 
concentration. An ideal nonmethane cutter would have a CH4 
penetration fraction, PFCH4, of 1.000, and the penetration 
fraction for all other nonmethane hydrocarbons would be 0.000, as 
represented by PFC2H6. The emission calculations in Sec. 
1065.660 use the measured values from this verification to account for 
less than ideal NMC performance.
    (c) System requirements. We do not limit NMC penetration fractions 
to a certain range. However, we recommend that you optimize a nonmethane 
cutter by adjusting its temperature to achieve a PFCH4 >0.85 
and a PFC2H6 <0.02, as determined by paragraphs (d), (e), or 
(f) of this section, as applicable. If we use a nonmethane cutter for 
testing, it will meet this recommendation. If adjusting NMC temperature 
does not result in achieving both of these specifications 
simultaneously, we recommend that you replace the catalyst material. Use 
the most recently determined penetration values from this section to 
calculate HC emissions according to Sec. 1065.660 and Sec. 1065.665 as 
applicable.
    (d) Procedure for a FID calibrated with the NMC. The method 
described in this paragraph (d) is recommended over the procedures 
specified in paragraphs (e) and (f) of this section. If your FID 
arrangement is such that a FID is always calibrated to measure 
CH4 with the NMC, then span that FID with the NMC using a 
CH4 span gas, set the product of that FID's CH4 
response factor and CH4 penetration fraction, 
RFPFCH4[NMC-FID], equal to 1.0 for all emission calculations, 
and determine its combined ethane (C2H6) response 
factor and penetration fraction, RFPFC2H6[NMC-FID] as 
follows:
    (1) Select CH4 and C2H6 analytical 
gas mixtures and ensure that both mixtures meet the specifications of 
Sec. 1065.750. Select a CH4 concentration that you would use 
for spanning the FID during emission testing and select a 
C2H6 concentration that is typical of the peak 
NMHC concentration expected at the hydrocarbon standard or equal to the 
THC analyzer's span value. For CH4 analyzers with multiple 
ranges, perform this procedure on the highest range used for emission 
testing.
    (2) Start, operate, and optimize the nonmethane cutter according to 
the manufacturer's instructions, including any temperature optimization.
    (3) Confirm that the FID analyzer meets all the specifications of 
Sec. 1065.360.
    (4) Start and operate the FID analyzer according to the 
manufacturer's instructions.
    (5) Zero and span the FID with the nonmethane cutter as you would 
during emission testing. Span the FID through the cutter by using 
CH4 span gas.
    (6) Introduce the C2H6 analytical gas mixture 
upstream of the nonmethane cutter. Use good engineering judgment to 
address the effect of hydrocarbon

[[Page 127]]

contamination if your point of introduction is vastly different from the 
point of zero/span gas introduction.
    (7) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the nonmethane cutter and to account for 
the analyzer's response.
    (8) While the analyzer measures a stable concentration, record 30 
seconds of sampled data. Calculate the arithmetic mean of these data 
points.
    (9) Divide the mean C2H6 concentration by the 
reference concentration of C2H6, converted to a 
C1 basis. The result is the C2H6 
combined response factor and penetration fraction, 
RFPFC2H6[NMC-FID]. Use this combined response factor and 
penetration fraction and the product of the CH4 response 
factor and CH4 penetration fraction, 
RFPFCH4[NMC-FID], set to 1.0 in emission calculations 
according to Sec. 1065.660(b)(2)(i), Sec. 1065.660(d)(1)(i), or Sec. 
1065.665, as applicable.
    (e) Procedure for a FID calibrated with propane, bypassing the NMC. 
If you use a single FID for THC and CH4 determination with an 
NMC that is calibrated with propane, C3H8, by 
bypassing the NMC, determine its penetration fractions, 
PFC2H6[NMC-FID] and PFCH4[NMC-FID], as follows:
    (1) Select CH4 and C2H6 analytical 
gas mixtures and ensure that both mixtures meet the specifications of 
Sec. 1065.750. Select a CH4 concentration that you would use 
for spanning the FID during emission testing and select a 
C2H6 concentration that is typical of the peak 
NMHC concentration expected at the hydrocarbon standard and the 
C2H6 concentration typical of the peak total 
hydrocarbon (THC) concentration expected at the hydrocarbon standard or 
equal to the THC analyzer's span value. For CH4 analyzers 
with multiple ranges, perform this procedure on the highest range used 
for emission testing.
    (2) Start and operate the nonmethane cutter according to the 
manufacturer's instructions, including any temperature optimization.
    (3) Confirm that the FID analyzer meets all the specifications of 
Sec. 1065.360.
    (4) Start and operate the FID analyzer according to the 
manufacturer's instructions.
    (5) Zero and span the FID as you would during emission testing. Span 
the FID by bypassing the cutter and by using C3H8 
span gas.
    (6) Introduce the C2H6 analytical gas mixture 
upstream of the nonmethane cutter. Use good engineering judgment to 
address the effect of hydrocarbon contamination if your point of 
introduction is vastly different from the point of zero/span gas 
introduction.
    (7) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the nonmethane cutter and to account for 
the analyzer's response.
    (8) While the analyzer measures a stable concentration, record 30 
seconds of sampled data. Calculate the arithmetic mean of these data 
points.
    (9) Reroute the flow path to bypass the nonmethane cutter, introduce 
the C2H6 analytical gas mixture, and repeat the 
steps in paragraph (e)(7) through (e)(8) of this section.
    (10) Divide the mean C2H6 concentration 
measured through the nonmethane cutter by the mean 
C2H6 concentration measured after bypassing the 
nonmethane cutter. The result is the C2H6 
penetration fraction, PFC2H6[NMC-FID]. Use this penetration 
fraction according to Sec. 1065.660(b)(2)(ii), Sec. 
1065.660(d)(1)(ii), or Sec. 1065.665, as applicable.
    (11) Repeat the steps in paragraphs (e)(6) through (e)(10) of this 
section, but with the CH4 analytical gas mixture instead of 
C2H6. The result will be the CH4 
penetration fraction, PFCH4[NMC-FID]. Use this penetration 
fraction according to Sec. 1065.660(b)(2)(ii), Sec. 
1065.660(c)(1)(ii), or Sec. 1065.665, as applicable.
    (f) Procedure for a FID calibrated with CH4, bypassing 
the NMC. If you use a FID with an NMC that is calibrated with 
CH4, by bypassing the NMC, determine its combined ethane 
(C2H6) response factor and penetration fraction, 
RFPFC2H6[NMC-FID], as well as its CH4 penetration 
fraction, PFCH4[NMC-FID], as follows:
    (1) Select CH4 and C2H6 analytical 
gas mixtures and ensure that both mixtures meet the specifications of 
Sec. 1065.750. Select a CH4 concentration that you would use 
for spanning the FID during emission testing and select a 
C2H6 concentration that is typical of

[[Page 128]]

the peak NMHC concentration expected at the hydrocarbon standard or 
equal to the THC analyzer's span value. For CH4 analyzers 
with multiple ranges, perform this procedure on the highest range used 
for emission testing.
    (2) Start and operate the nonmethane cutter according to the 
manufacturer's instructions, including any temperature optimization.
    (3) Confirm that the FID analyzer meets all the specifications of 
Sec. 1065.360.
    (4) Start and operate the FID analyzer according to the 
manufacturer's instructions.
    (5) Zero and span the FID as you would during emission testing. Span 
the FID by bypassing the cutter and by using CH4 span gas. 
Note that you must span the FID on a C1 basis. For example, 
if your span gas has a methane reference value of 100 [micro] mol/mol, 
the correct FID response to that span gas is 100 [micro] mol/mol because 
there is one carbon atom per CH4 molecule.
    (6) Introduce the C2H6 analytical gas mixture 
upstream of the nonmethane cutter. Use good engineering judgment to 
address the effect of hydrocarbon contamination if your point of 
introduction is vastly different from the point of zero/span gas 
introduction.
    (7) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the nonmethane cutter and to account for 
the analyzer's response.
    (8) While the analyzer measures a stable concentration, record 30 
seconds of sampled data. Calculate the arithmetic mean of these data 
points.
    (9) Divide the mean C2H6 concentration by the 
reference concentration of C2H6, converted to a 
C1 basis. The result is the C2H6 
combined response factor and penetration fraction, 
RFPFC2H6[NMC-FID]. Use this combined response factor and 
penetration fraction according to Sec. 1065.660(b)(2)(iii), Sec. 
1065.660(d)(1)(iii), or Sec. 1065.665, as applicable.
    (10) Introduce the CH4 analytical gas mixture upstream of 
the nonmethane cutter. Use good engineering judgment to address the 
effect of hydrocarbon contamination if your point of introduction is 
vastly different from the point of zero/span gas introduction.
    (11) Allow time for the analyzer response to stabilize. 
Stabilization time may include time to purge the nonmethane cutter and 
to account for the analyzer's response.
    (12) While the analyzer measures a stable concentration, record 30 
seconds of sampled data. Calculate the arithmetic mean of these data 
points.
    (13) Reroute the flow path to bypass the nonmethane cutter, 
introduce the CH4 analytical gas mixture, and repeat the 
steps in paragraphs (e)(11) and (12) of this section.
    (14) Divide the mean CH4 concentration measured through 
the nonmethane cutter by the mean CH4 concentration measured 
after bypassing the nonmethane cutter. The result is the CH4 
penetration fraction, PFCH4[NMC-FID]. Use this penetration 
fraction according to Sec. 1065.660(b)(2)(iii), Sec. 
1065.660(d)(1)(iii), or Sec. 1065.665, as applicable.

[73 FR 37310, June 30, 2008, as amended at 74 FR 56513, Oct. 30, 2009; 
79 FR 23770, Apr. 28, 2014; 81 FR 74168, Oct. 25, 2016]



Sec. 1065.366  Interference verification for FTIR analyzers.

    (a) Scope and frequency. If you measure CH4, 
C2H6, NMHC, or NMNEHC using an FTIR analyzer, 
verify the amount of interference after initial analyzer installation 
and after major maintenance.
    (b) Measurement principles. Interference gases can interfere with 
certain analyzers by causing a response similar to the target analyte. 
If the analyzer uses compensation algorithms that utilize measurements 
of other gases to meet this interference verification, simultaneously 
conduct these other measurements to test the compensation algorithms 
during the analyzer interference verification.
    (c) System requirements. An FTIR analyzer must have combined 
interference that is within [2% of the flow-weighted mean concentration 
of CH4, NMHC, or NMNEHC expected at the standard, though we 
strongly recommend a lower interference that is within [1%.
    (d) Procedure. Perform the interference verification for an FTIR 
analyzer using the same procedure that applies for N2O 
analyzers in Sec. 1065.375(d).

[81 FR 74168, Oct. 25, 2016]

[[Page 129]]



Sec. 1065.369  H[bdi2] O, CO, and CO[bdi2] interference verification
for photoacoustic alcohol analyzers.

    (a) Scope and frequency. If you measure ethanol or methanol using a 
photoacoustic analyzer, verify the amount of H2O, CO, and 
CO2 interference after initial analyzer installation and 
after major maintenance.
    (b) Measurement principles. H2O, CO, and CO2 
can positively interfere with a photoacoustic analyzer by causing a 
response similar to ethanol or methanol. If the photoacoustic analyzer 
uses compensation algorithms that utilize measurements of other gases to 
meet this interference verification, simultaneously conduct these other 
measurements to test the compensation algorithms during the analyzer 
interference verification.
    (c) System requirements. Photoacoustic analyzers must have combined 
interference that is within (0.0 [0.5) [micro] mol/mol. We strongly 
recommend a lower interference that is within (0.0 [0.25) [micro] mol/
mol.
    (d) Procedure. Perform the interference verification by following 
the procedure in Sec. 1065.375(d), comparing the results to paragraph 
(c) of this section.

[79 FR 23770, Apr. 28, 2014]

             NOX and N2O Measurements



Sec. 1065.370  CLD CO[bdi2] and H[bdi2] O quench verification.

    (a) Scope and frequency. If you use a CLD analyzer to measure 
NOX, verify the amount of H2O and CO2 
quench after installing the CLD analyzer and after major maintenance.
    (b) Measurement principles. H2O and CO2 can 
negatively interfere with a CLD's NOX response by collisional 
quenching, which inhibits the chemiluminescent reaction that a CLD 
utilizes to detect NOX. This procedure and the calculations 
in Sec. 1065.675 determine quench and scale the quench results to the 
maximum mole fraction of H2O and the maximum CO2 
concentration expected during emission testing. If the CLD analyzer uses 
quench compensation algorithms that utilize H2O and/or 
CO2 measurement instruments, evaluate quench with these 
instruments active and evaluate quench with the compensation algorithms 
applied.
    (c) System requirements. A CLD analyzer must have a combined 
H2O and CO2 quench of [2% or less, though we 
strongly recommend a quench of [1% or less. Combined quench is the sum 
of the CO2 quench determined as described in paragraph (d) of 
this section, plus the H2O quench determined in paragraph (e) 
of this section.
    (d) CO2 quench verification procedure. Use the following 
method to determine CO2 quench by using a gas divider that 
blends binary span gases with zero gas as the diluent and meets the 
specifications in Sec. 1065.248, or use good engineering judgment to 
develop a different protocol:
    (1) Use PTFE or stainless steel tubing to make necessary 
connections.
    (2) Configure the gas divider such that nearly equal amounts of the 
span and diluent gases are blended with each other.
    (3) If the CLD analyzer has an operating mode in which it detects 
NO-only, as opposed to total NOX, operate the CLD analyzer in 
the NO-only operating mode.
    (4) Use a CO2 span gas that meets the specifications of 
Sec. 1065.750 and a concentration that is approximately twice the 
maximum CO2 concentration expected during emission testing.
    (5) Use an NO span gas that meets the specifications of Sec. 
1065.750 and a concentration that is approximately twice the maximum NO 
concentration expected during emission testing.
    (6) Zero and span the CLD analyzer. Span the CLD analyzer with the 
NO span gas from paragraph (d)(5) of this section through the gas 
divider. Connect the NO span gas to the span port of the gas divider; 
connect a zero gas to the diluent port of the gas divider; use the same 
nominal blend ratio selected in paragraph (d)(2) of this section; and 
use the gas divider's output concentration of NO to span the CLD 
analyzer. Apply gas property corrections as necessary to ensure accurate 
gas division.
    (7) Connect the CO2 span gas to the span port of the gas 
divider.
    (8) Connect the NO span gas to the diluent port of the gas divider.
    (9) While flowing NO and CO2 through the gas divider, 
stabilize the output of

[[Page 130]]

the gas divider. Determine the CO2 concentration from the gas 
divider output, applying gas property correction as necessary to ensure 
accurate gas division, or measure it using an NDIR. Record this 
concentration, xCO2act, and use it in the quench verification 
calculations in Sec. 1065.675. Alternatively, you may use a simple gas 
blending device and use an NDIR to determine this CO2 
concentration. If you use an NDIR, it must meet the requirements of this 
part for laboratory testing and you must span it with the CO2 
span gas from paragraph (d)(4) of this section.
    (10) Measure the NO concentration downstream of the gas divider with 
the CLD analyzer. Allow time for the analyzer response to stabilize. 
Stabilization time may include time to purge the transfer line and to 
account for analyzer response. While the analyzer measures the sample's 
concentration, record the analyzer's output for 30 seconds. Calculate 
the arithmetic mean concentration from these data, xNOmeas. 
Record xNOmeas, and use it in the quench verification 
calculations in Sec. 1065.675.
    (11) Calculate the actual NO concentration at the gas divider's 
outlet, xNOact, based on the span gas concentrations and 
xCO2act according to Eq. 1065.675-2. Use the calculated value 
in the quench verification calculations in Eq. 1065.675-1.
    (12) Use the values recorded according to this paragraph (d) and 
paragraph (e) of this section to calculate quench as described in Sec. 
1065.675.
    (e) H2O quench verification procedure. Use the following 
method to determine H2O quench, or use good engineering 
judgment to develop a different protocol:
    (1) Use PTFE or stainless steel tubing to make necessary 
connections.
    (2) If the CLD analyzer has an operating mode in which it detects 
NO-only, as opposed to total NOX, operate the CLD analyzer in 
the NO-only operating mode.
    (3) Use an NO span gas that meets the specifications of Sec. 
1065.750 and a concentration that is near the maximum concentration 
expected during emission testing.
    (4) Zero and span the CLD analyzer. Span the CLD analyzer with the 
NO span gas from paragraph (e)(3) of this section, record the span gas 
concentration as xNOdry, and use it in the quench 
verification calculations in Sec. 1065.675.
    (5) Humidify the NO span gas by bubbling it through distilled 
H2O in a sealed vessel. If the humidified NO span gas sample 
does not pass through a sample dryer for this verification test, control 
the vessel temperature to generate an H2O level approximately 
equal to the maximum mole fraction of H2O expected during 
emission testing. If the humidified NO span gas sample does not pass 
through a sample dryer, the quench verification calculations in Sec. 
1065.675 scale the measured H2O quench to the highest mole 
fraction of H2O expected during emission testing. If the 
humidified NO span gas sample passes through a dryer for this 
verification test, control the vessel temperature to generate an 
H2O level at least as high as the level determined in Sec. 
1065.145(e)(2). For this case, the quench verification calculations in 
Sec. 1065.675 do not scale the measured H2O quench.
    (6) Introduce the humidified NO test gas into the sample system. You 
may introduce it upstream or downstream of any sample dryer that is used 
during emission testing. Note that the sample dryer must meet the sample 
dryer verification check in Sec. 1065.342.
    (7) Measure the mole fraction of H2O in the humidified NO 
span gas downstream of the sample dryer, xH2Omeas. We 
recommend that you measure xH2Omeas as close as possible to 
the CLD analyzer inlet. You may calculate xH2Omeas from 
measurements of dew point, Tdew, and absolute pressure, 
ptotal.
    (8) Use good engineering judgment to prevent condensation in the 
transfer lines, fittings, or valves from the point where 
xH2Omeas is measured to the analyzer. We recommend that you 
design your system so the wall temperatures in the transfer lines, 
fittings, and valves from the point where xH2Omeas is 
measured to the analyzer are at least 5  deg.C above the local sample 
gas dew point.
    (9) Measure the humidified NO span gas concentration with the CLD 
analyzer. Allow time for the analyzer response to stabilize. 
Stabilization time may include time to purge the transfer

[[Page 131]]

line and to account for analyzer response. While the analyzer measures 
the sample's concentration, record the analyzer's output for 30 seconds. 
Calculate the arithmetic mean of these data, xNOwet. Record 
xNOwet and use it in the quench verification calculations in 
Sec. 1065.675.
    (f) Corrective action. If the sum of the H2O quench plus 
the CO2 quench is less than -2% or greater than + 2%, take 
corrective action by repairing or replacing the analyzer. Before running 
emission tests, verify that the corrective action successfully restored 
the analyzer to proper functioning.
    (g) Exceptions. The following exceptions apply:
    (1) You may omit this verification if you can show by engineering 
analysis that for your NOX sampling system and your emission 
calculation procedures, the combined CO2 and H2O 
interference for your NOX CLD analyzer always affects your 
brake-specific NOX emission results within no more than [1% 
of the applicable NOX standard. If you certify to a combined 
emission standard (such as a NOX + NMHC standard), scale your 
NOX results to the combined standard based on the measured 
results (after incorporating deterioration factors, if applicable). For 
example, if your final NOX + NMHC value is half of the 
emission standard, double the NOX result to estimate the 
level of NOX emissions corresponding to the applicable 
standard.
    (2) You may use a NOX CLD analyzer that you determine 
does not meet this verification, as long as you try to correct the 
problem and the measurement deficiency does not adversely affect your 
ability to show that engines comply with all applicable emission 
standards.

[73 FR 59328, Oct. 8, 2008, as amended at 73 FR 73789, Dec. 4, 2008; 75 
FR 23041, Apr. 30, 2010; 76 FR 57447, Sept. 15, 2011; 79 FR 23771, Apr. 
28, 2014; 81 FR 74168, Oct. 25, 2016]



Sec. 1065.372  NDUV analyzer HC and H[bdi2] O interference verification.

    (a) Scope and frequency. If you measure NOX using an NDUV 
analyzer, verify the amount of H2O and hydrocarbon 
interference after initial analyzer installation and after major 
maintenance.
    (b) Measurement principles. Hydrocarbons and H2O can 
positively interfere with an NDUV analyzer by causing a response similar 
to NOX. If the NDUV analyzer uses compensation algorithms 
that utilize measurements of other gases to meet this interference 
verification, simultaneously conduct such measurements to test the 
algorithms during the analyzer interference verification.
    (c) System requirements. A NOX NDUV analyzer must have 
combined H2O and HC interference within [2% of the flow-
weighted mean concentration of NOX expected at the standard, 
though we strongly recommend keeping interference within [1%.
    (d) Procedure. Perform the interference verification as follows:
    (1) Start, operate, zero, and span the NOX NDUV analyzer 
according to the instrument manufacturer's instructions.
    (2) We recommend that you extract engine exhaust to perform this 
verification. Use a CLD that meets the specifications of subpart C of 
this part to quantify NOX in the exhaust. Use the CLD 
response as the reference value. Also measure HC in the exhaust with a 
FID analyzer that meets the specifications of subpart C of this part. 
Use the FID response as the reference hydrocarbon value.
    (3) Upstream of any sample dryer, if one is used during testing, 
introduce the engine exhaust to the NDUV analyzer.
    (4) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the transfer line and to account for 
analyzer response.
    (5) While all analyzers measure the sample's concentration, record 
30 seconds of sampled data, and calculate the arithmetic means for the 
three analyzers.
    (6) Subtract the CLD mean from the NDUV mean.
    (7) Multiply this difference by the ratio of the flow-weighted mean 
HC concentration expected at the standard to the HC concentration 
measured during the verification. The analyzer meets the interference 
verification of this section if this result is within [2%

[[Page 132]]

of the NOX concentration expected at the standard.
    (e) Exceptions. The following exceptions apply:
    (1) You may omit this verification if you can show by engineering 
analysis that for your NOX sampling system and your emission 
calculation procedures, the combined HC and H2O interference 
for your NOX NDUV analyzer always affects your brake-specific 
NOX emission results by less than 0.5% of the applicable 
NOX standard.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37312, June 30, 2008; 
76 FR 57447, Sept. 15, 2011]



Sec. 1065.375  Interference verification for N[bdi2] O analyzers.

    (a) Scope and frequency. See Sec. 1065.275 to determine whether you 
need to verify the amount of interference after initial analyzer 
installation and after major maintenance.
    (b) Measurement principles. Interference gases can positively 
interfere with certain analyzers by causing a response similar to 
N2O. If the analyzer uses compensation algorithms that 
utilize measurements of other gases to meet this interference 
verification, simultaneously conduct these other measurements to test 
the compensation algorithms during the analyzer interference 
verification.
    (c) System requirements. Analyzers must have combined interference 
that is within (0.0 [1.0) [micro] mol/mol. We strongly recommend a lower 
interference that is within (0.0 [0.5) [micro] mol/mol.
    (d) Procedure. Perform the interference verification as follows:
    (1) Start, operate, zero, and span the N2O analyzer as 
you would before an emission test. If the sample is passed through a 
dryer during emission testing, you may run this verification test with 
the dryer if it meets the requirements of Sec. 1065.342. Operate the 
dryer at the same conditions as you will for an emission test. You may 
also run this verification test without the sample dryer.
    (2) Create a humidified test gas by bubbling a multi component span 
gas that incorporates the target interference species and meets the 
specifications in Sec. 1065.750 through distilled H2O in a 
sealed vessel. If the sample is not passed through a dryer during 
emission testing, control the vessel temperature to generate an 
H2O level at least as high as the maximum expected during 
emission testing. If the sample is passed through a dryer during 
emission testing, control the vessel temperature to generate an 
H2O level at least as high as the level determined in Sec. 
1065.145(e)(2) for that dryer. Use interference span gas concentrations 
that are at least as high as the maximum expected during testing.
    (3) Introduce the humidified interference test gas into the sample 
system. You may introduce it downstream of any sample dryer, if one is 
used during testing.
    (4) If the sample is not passed through a dryer during this 
verification test, measure the H2O mole 
fraction,xH2O, of the humidified interference test 
gas as close as possible to the inlet of the analyzer. For example, 
measure dewpoint, Tdew, and absolute pressure, 
ptotal, to calculatexH2O. Verify that 
the H2O content meets the requirement in paragraph (d)(2) of 
this section. If the sample is passed through a dryer during this 
verification test, you must verify that the H2O content of 
the humidified test gas downstream of the vessel meets the requirement 
in paragraph (d)(2) of this section based on either direct measurement 
of the H2O content (e.g., dewpoint and pressure) or an 
estimate based on the vessel pressure and temperature. Use good 
engineering judgment to estimate the H2O content. For 
example, you may use previous direct measurements of H2O 
content to verify the vessel's level of saturation.
    (5) If a sample dryer is not used in this verification test, use 
good engineering judgment to prevent condensation in the transfer lines, 
fittings, or valves from the point wherexH2O is 
measured to the analyzer. We recommend that you design your system so 
that the wall temperatures in the transfer lines, fittings, and valves 
from the point where xH2O is measured to the 
analyzer are at least 5 [ordm]C above the local sample gas dewpoint.
    (6) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the transfer

[[Page 133]]

line and to account for analyzer response.
    (7) While the analyzer measures the sample's concentration, record 
its output for 30 seconds. Calculate the arithmetic mean of this data. 
When performed with all the gases simultaneously, this is the combined 
interference.
    (8) The analyzer meets the interference verification if the result 
of paragraph (d)(7) of this section meets the tolerance in paragraph (c) 
of this section.
    (9) You may also run interference procedures separately for 
individual interference gases. If the interference gas levels used are 
higher than the maximum levels expected during testing, you may scale 
down each observed interference value (the arithmetic mean of 30 second 
data described in paragraph (d)(7) of this section) by multiplying the 
observed interference by the ratio of the maximum expected concentration 
value to the actual value used during this procedure. You may run 
separate interference concentrations of H2O (down to 0.025 
mol/mol H2O content) that are lower than the maximum levels 
expected during testing, but you must scale up the observed 
H2O interference by multiplying the observed interference by 
the ratio of the maximum expected H2O concentration value to 
the actual value used during this procedure. The sum of the scaled 
interference values must meet the tolerance for combined interference as 
specified in paragraph (c) of this section.

[74 FR 56515, Oct. 30, 2009, as amended at 23771, Apr. 28, 2014; 81 FR 
74168, Oct. 25, 2016]



Sec. 1065.376  Chiller NO[bdi2] penetration.

    (a) Scope and frequency. If you use a chiller to dry a sample 
upstream of a NOX measurement instrument, but you don't use 
an NO2-to-NO converter upstream of the chiller, you must 
perform this verification for chiller NO2 penetration. 
Perform this verification after initial installation and after major 
maintenance.
    (b) Measurement principles. A chiller removes H2O, which 
can otherwise interfere with a NOX measurement. However, 
liquid H2O remaining in an improperly designed chiller can 
remove NO2 from the sample. If a chiller is used without an 
NO2-to-NO converter upstream, it could remove NO2 
from the sample prior NOX measurement.
    (c) System requirements. A chiller must allow for measuring at least 
95% of the total NO2 at the maximum expected concentration of 
NO2.
    (d) Procedure. Use the following procedure to verify chiller 
performance:
    (1) Instrument setup. Follow the analyzer and chiller manufacturers' 
start-up and operating instructions. Adjust the analyzer and chiller as 
needed to optimize performance.
    (2) Equipment setup and data collection. (i) Zero and span the total 
NOX gas analyzer(s) as you would before emission testing.
    (ii) Select an NO2 calibration gas, balance gas of dry 
air, that has an NO2 concentration within [5% of the maximum 
NO2 concentration expected during testing.
    (iii) Overflow this calibration gas at the gas sampling system's 
probe or overflow fitting. Allow for stabilization of the total 
NOX response, accounting only for transport delays and 
instrument response.
    (iv) Calculate the mean of 30 seconds of recorded total 
NOX data and record this value as xNOXref.
    (v) Stop flowing the NO2 calibration gas.
    (vi) Next saturate the sampling system by overflowing a dewpoint 
generator's output, set at a dewpoint of 50  deg.C, to the gas sampling 
system's probe or overflow fitting. Sample the dewpoint generator's 
output through the sampling system and chiller for at least 10 minutes 
until the chiller is expected to be removing a constant rate of 
H2O.
    (vii) Immediately switch back to overflowing the NO2 
calibration gas used to establish xNOxref. Allow for 
stabilization of the total NOX response, accounting only for 
transport delays and instrument response. Calculate the mean of 30 
seconds of recorded total NOX data and record this value as 
xNOxmeas.
    (viii) Correct xNOxmeas to xNOxdry based upon 
the residual H2O vapor that passed through the chiller at the 
chiller's outlet temperature and pressure.

[[Page 134]]

    (3) Performance evaluation. If xNOxdry is less than 95% 
of xNOxref, repair or replace the chiller.
    (e) Exceptions. The following exceptions apply:
    (1) You may omit this verification if you can show by engineering 
analysis that for your NOX sampling system and your emission 
calculations procedures, the chiller always affects your brake-specific 
NOX emission results by less than 0.5% of the applicable 
NOX standard.
    (2) You may use a chiller that you determine does not meet this 
verification, as long as you try to correct the problem and the 
measurement deficiency does not adversely affect your ability to show 
that engines comply with all applicable emission standards.

[73 FR 37312, June 30, 2008, as amended at 79 FR 23771, Apr. 28, 2014]



Sec. 1065.378  NO[bdi2] -to-NO converter conversion verification.

    (a) Scope and frequency. If you use an analyzer that measures only 
NO to determine NOX, you must use an NO2-to-NO 
converter upstream of the analyzer. Perform this verification after 
installing the converter, after major maintenance and within 35 days 
before an emission test. This verification must be repeated at this 
frequency to verify that the catalytic activity of the NO2-
to-NO converter has not deteriorated.
    (b) Measurement principles. An NO2-to-NO converter allows 
an analyzer that measures only NO to determine total NOX by 
converting the NO2 in exhaust to NO.
    (c) System requirements. An NO2-to-NO converter must 
allow for measuring at least 95% of the total NO2 at the 
maximum expected concentration of NO2.
    (d) Procedure. Use the following procedure to verify the performance 
of a NO2-to-NO converter:
    (1) Instrument setup. Follow the analyzer and NO2-to-NO 
converter manufacturers' start-up and operating instructions. Adjust the 
analyzer and converter as needed to optimize performance.
    (2) Equipment setup. Connect an ozonator's inlet to a zero-air or 
oxygen source and connect its outlet to one port of a three-way tee 
fitting. Connect an NO span gas to another port, and connect the 
NO2-to-NO converter inlet to the last port.
    (3) Adjustments and data collection. Perform this check as follows:
    (i) Set ozonator air off, turn ozonator power off, and set the 
analyzer to NO mode. Allow for stabilization, accounting only for 
transport delays and instrument response.
    (ii) Use an NO concentration that is representative of the peak 
total NOX concentration expected during testing. The 
NO2 content of the gas mixture shall be less than 5% of the 
NO concentration. Record the concentration of NO by calculating the mean 
of 30 seconds of sampled data from the analyzer and record this value as 
xNOref.
    (iii) Turn on the ozonator O2 supply and adjust the 
O2 flow rate so the NO indicated by the analyzer is about 10 
percent less than xNOref. Record the concentration of NO by 
calculating the mean of 30 seconds of sampled data from the analyzer and 
record this value as xNO + O2mix.
    (iv) Switch the ozonator on and adjust the ozone generation rate so 
the NO measured by the analyzer is 20 percent of xNOref or a 
value which would simulate the maximum concentration of NO2 
expected during testing, while maintaining at least 10 percent unreacted 
NO. This ensures that the ozonator is generating NO2 at the 
maximum concentration expected during testing. Record the concentration 
of NO by calculating the mean of 30 seconds of sampled data from the 
analyzer and record this value as xNOmeas.
    (v) Switch the NOX analyzer to NOX mode and 
measure total NOX. Record the concentration of NOX 
by calculating the mean of 30 seconds of sampled data from the analyzer 
and record this value as xNOxmeas.
    (vi) Switch off the ozonator but maintain gas flow through the 
system. The NOX analyzer will indicate the NOX in 
the NO + O2 mixture. Record the concentration of 
NOX by calculating the mean of 30 seconds of sampled data 
from the analyzer and record this value as xNOx + O2mix.
    (vii) Turn off the ozonator O2 supply. The NOX 
analyzer will indicate the NOX in the original NO-in-
N2 mixture. Record the concentration of NOX by

[[Page 135]]

calculating the mean of 30 seconds of sampled data from the analyzer and 
record this value as xNOxref. This value should be no more 
than 5 percent above the xNOref value.
    (4) Performance evaluation. Calculate the efficiency of the 
NOX converter by substituting the concentrations obtained 
into the following equation:
[GRAPHIC] [TIFF OMITTED] TR08OC08.097

    (5) If the result is less than 95%, repair or replace the 
NO2-to-NO converter.
    (e) Exceptions. The following exceptions apply:
    (1) You may omit this verification if you can show by engineering 
analysis that for your NOX sampling system and your emission 
calculations procedures, the converter always affects your brake-
specific NOX emission results by less than 0.5% of the 
applicable NOX standard.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37313, June 30, 2008; 
73 FR 59330, Oct. 8, 2008; 76 FR 57447, Sept. 15, 2011]

                             PM Measurements



Sec. 1065.390  PM balance verifications and weighing process 
verification.

    (a) Scope and frequency. This section describes three verifications.
    (1) Independent verification of PM balance performance within 370 
days before weighing any filter.
    (2) Zero and span the balance within 12 h before weighing any 
filter.
    (3) Verify that the mass determination of reference filters before 
and after a filter weighing session are less than a specified tolerance.
    (b) Independent verification. Have the balance manufacturer (or a 
representative approved by the balance manufacturer) verify the balance 
performance within 370 days of testing. Balances have internal weights 
that compensate for drift due to environmental changes. These internal 
weights must be verified as part of this independent verification with 
external, certified calibration weights that meet the specifications in 
Sec. 1065.790.
    (c) Zeroing and spanning. You must verify balance performance by 
zeroing and spanning it with at least one calibration weight. Also, any 
external weights you use must meet the specifications in Sec. 1065.790. 
Any weights internal to the PM balance used for this verification must 
be verified as described in paragraph (b) of this section.
    (1) Use a manual procedure in which you zero the balance and span 
the balance with at least one calibration weight. If you normally use 
mean values by repeating the weighing process to improve the accuracy 
and precision of PM measurements, use the same process to verify balance 
performance.
    (2) You may use an automated procedure to verify balance 
performance. For example most balances have internal weights for 
automatically verifying balance performance.
    (d) Reference sample weighing. Verify all mass readings during a 
weighing session by weighing reference PM sample media (e.g., filters) 
before and after a weighing session. A weighing session may be as short 
as desired, but no longer than 80 hours, and may include both pre-test 
and post-test mass readings. We recommend that weighing sessions be 
eight hours or less. Successive mass determinations of each reference PM 
sample media (e.g., filter) must return the same value within [10 
[micro] g or [10% of the net PM mass expected at the standard (if 
known), whichever is higher. If successive reference PM sample media 
(e.g., filter) weighing events fail this criterion, invalidate all 
individual test media (e.g., filter) mass readings occurring between the 
successive reference media (e.g., filter) mass determinations. You may 
reweigh these media (e.g., filter) in another weighing session. If you 
invalidate a

[[Page 136]]

pre-test media (e.g., filter) mass determination, that test interval is 
void. Perform this verification as follows:
    (1) Keep at least two samples of unused PM sample media (e.g., 
filters) in the PM-stabilization environment. Use these as references. 
If you collect PM with filters, select unused filters of the same 
material and size for use as references. You may periodically replace 
references, using good engineering judgment.
    (2) Stabilize references in the PM stabilization environment. 
Consider references stabilized if they have been in the PM-stabilization 
environment for a minimum of 30 min, and the PM-stabilization 
environment has been within the specifications of Sec. 1065.190(d) for 
at least the preceding 60 min.
    (3) Exercise the balance several times with a reference sample. We 
recommend weighing ten samples without recording the values.
    (4) Zero and span the balance. Using good engineering judgment, 
place a test mass such as a calibration weight on the balance, then 
remove it. After spanning, confirm that the balance returns to a zero 
reading within the normal stabilization time.
    (5) Weigh each of the reference media (e.g., filters) and record 
their masses. We recommend using substitution weighing as described in 
Sec. 1065.590(j). If you normally use mean values by repeating the 
weighing process to improve the accuracy and precision of the reference 
media (e.g., filter) mass, you must use mean values of sample media 
(e.g., filter) masses.
    (6) Record the balance environment dewpoint, ambient temperature, 
and atmospheric pressure.
    (7) Use the recorded ambient conditions to correct results for 
buoyancy as described in Sec. 1065.690. Record the buoyancy-corrected 
mass of each of the references.
    (8) Subtract each reference media's (e.g., filter's) buoyancy-
corrected reference mass from its previously measured and recorded 
buoyancy-corrected mass.
    (9) If any of the reference filters' observed mass changes by more 
than that allowed under this paragraph, you must invalidate all PM mass 
determinations made since the last successful reference media (e.g. 
filter) mass validation. You may discard reference PM media (e.g. 
filters) if only one of the filter's mass changes by more than the 
allowable amount and you can positively identify a special cause for 
that filter's mass change that would not have affected other in-process 
filters. Thus, the validation can be considered a success. In this case, 
you do not have to include the contaminated reference media when 
determining compliance with paragraph (d)(10) of this section, but the 
affected reference filter must be immediately discarded and replaced 
prior to the next weighing session.
    (10) If any of the reference masses change by more than that allowed 
under this paragraph (d), invalidate all PM results that were determined 
between the two times that the reference masses were determined. If you 
discarded reference PM sample media according to paragraph (d)(9) of 
this section, you must still have at least one reference mass difference 
that meets the criteria in this paragraph (d). Otherwise, you must 
invalidate all PM results that were determined between the two times 
that the reference media (e.g., filters) masses were determined.

[73 FR 37313, June 30, 2008, as amended at 75 FR 23042, Apr. 30, 2010; 
75 FR 68463, Nov. 8, 2010; 81 FR 74168, Oct. 25, 2016]



Sec. 1065.395  Inertial PM balance verifications.

    This section describes how to verify the performance of an inertial 
PM balance.
    (a) Independent verification. Have the balance manufacturer (or a 
representative approved by the balance manufacturer) verify the inertial 
balance performance within 370 days before testing.
    (b) Other verifications. Perform other verifications using good 
engineering judgment and instrument manufacturer recommendations.



        Subpart E_Engine Selection, Preparation, and Maintenance



Sec. 1065.401  Test engine selection.

    While all engine configurations within a certified engine family 
must comply with the applicable standards in

[[Page 137]]

the standard-setting part, you need not test each configuration for 
certification.
    (a) Select an engine configuration within the engine family for 
testing, as follows:
    (1) Test the engine that we specify, whether we issue general 
guidance or give you specific instructions.
    (2) If we do not tell you which engine to test, follow any 
instructions in the standard-setting part.
    (3) If we do not tell you which engine to test and the standard-
setting part does not include specifications for selecting test engines, 
use good engineering judgment to select the engine configuration within 
the engine family that is most likely to exceed an emission standard.
    (b) In the absence of other information, the following 
characteristics are appropriate to consider when selecting the engine to 
test:
    (1) Maximum fueling rates.
    (2) Maximum loads.
    (3) Maximum in-use speeds.
    (4) Highest sales volume.
    (c) For our testing, we may select any engine configuration within 
the engine family.



Sec. 1065.405  Test engine preparation and maintenance.

    This part 1065 describes how to test engines for a variety of 
purposes, including certification testing, production-line testing, and 
in-use testing. Depending on which type of testing is being conducted, 
different preparation and maintenance requirements apply for the test 
engine.
    (a) If you are testing an emission-data engine for certification, 
make sure it is built to represent production engines, consistent with 
paragraph (f) of this section. This includes governors that you normally 
install on production engines. Production engines should also be tested 
with their installed governors. If your engine is equipped with multiple 
user-selectable governor types and if the governor does not manipulate 
the emission control system (i.e., the governor only modulates an 
``operator demand'' signal such as commanded fuel rate, torque, or 
power), choose the governor type that allows the test cell to most 
accurately follow the duty cycle. If the governor manipulates the 
emission control system, treat it as an adjustable parameter. See 
paragraph (b) of this section for guidance on setting adjustable 
parameters. If you do not install governors on production engines, 
simulate a governor that is representative of a governor that others 
will install on your production engines. In certain circumstances, you 
may incorporate test cell components to simulate an in-use 
configuration, consistent with good engineering judgment. For example, 
Sec. Sec. 1065.122 and 1065.125 allow the use of test cell components 
to represent engine cooling and intake air systems. The provisions in 
Sec. 1065.110(e) also apply to emission-data engines for certification.
    (b) We may set adjustable parameters to any value in the valid 
range, and you are responsible for controlling emissions over the full 
valid range. For each adjustable parameter, if the standard-setting part 
has no unique requirements and if we have not specified a value, use 
good engineering judgment to select the most common setting. If 
information on the most common setting is not available, select the 
setting representing the engine's original shipped configuration. If 
information on the most common and original settings is not available, 
set the adjustable parameter in the middle of the valid range.
    (c) Testing generally occurs only after the test engine has 
undergone a stabilization step (or in-use operation). If the engine has 
not already been stabilized, run the test engine, with all emission 
control systems operating, long enough to stabilize emission levels. 
Note that you must generally use the same stabilization procedures for 
emission-data engines for which you apply the same deterioration factors 
so low-hour emission-data engines are consistent with the low-hour 
engine used to develop the deterioration factor.
    (1) Unless otherwise specified in the standard-setting part, you may 
consider emission levels stable without measurement after 50 h of 
operation. If the engine needs less operation to stabilize emission 
levels, record your reasons and the methods for doing this,

[[Page 138]]

and give us these records if we ask for them. If the engine will be 
tested for certification as a low-hour engine, see the standard-setting 
part for limits on testing engines to establish low-hour emission 
levels.
    (2) You may stabilize emissions from a catalytic exhaust 
aftertreatment device by operating it on a different engine, consistent 
with good engineering judgment. Note that good engineering judgment 
requires that you consider both the purpose of the test and how your 
stabilization method will affect the development and application of 
deterioration factors. For example, this method of stabilization is 
generally not appropriate for production engines. We may also allow you 
to stabilize emissions from a catalytic exhaust aftertreatment device by 
operating it on an engine-exhaust simulator.
    (d) Record any maintenance, modifications, parts changes, diagnostic 
or emissions testing and document the need for each event. You must 
provide this information if we request it.
    (e) For accumulating operating hours on your test engines, select 
engine operation that represents normal in-use operation for the engine 
family.
    (f) If your engine will be used in a vehicle equipped with a 
canister for storing evaporative hydrocarbons for eventual combustion in 
the engine and the test sequence involves a cold-start or hot-start duty 
cycle, attach a canister to the engine before running an emission test. 
You may omit using an evaporative canister for any hot-stabilized duty 
cycles. You may request to omit using an evaporative canister during 
testing if you can show that it would not affect your ability to show 
compliance with the applicable emission standards. You may operate the 
engine without an installed canister for service accumulation. Prior to 
an emission test, use the following steps to precondition a canister and 
attach it to your engine:
    (1) Use a canister and plumbing arrangement that represents the in-
use configuration of the largest capacity canister in all expected 
applications.
    (2) Precondition the canister as described in 40 CFR 86.132-96(j).
    (3) Connect the canister's purge port to the engine.
    (4) Plug the canister port that is normally connected to the fuel 
tank.
    (g) This paragraph (g) defines the components that are considered to 
be part of the engine for laboratory testing. See Sec. 1065.110 for 
provisions related to system boundaries with respect to work inputs and 
outputs.
    (1) This paragraph (g)(1) describes certain criteria for considering 
a component to be part of the test engine. The criteria are intended to 
apply broadly, such that a component would generally be considered part 
of the engine in cases of uncertainty. Except as specified in paragraph 
(g)(2) of this section, an engine-related component meeting both the 
following criteria is considered to be part of the test engine for 
purposes of testing and for stabilizing emission levels, 
preconditioning, and measuring emission levels:
    (i) The component directly affects the functioning of the engine, is 
related to controlling emissions, or transmits engine power. This would 
include engine cooling systems, engine controls, and transmissions.
    (ii) The component is covered by the applicable certificate of 
conformity. For example, this criterion would typically exclude 
radiators not described in an application for certification.
    (2) This paragraph (g)(2) applies for engine-related components that 
meet the criteria of paragraph (g)(1) of this section, but that are part 
of the laboratory setup or are used for other engines. Such components 
are considered to be part of the test engine for preconditioning, but 
not for engine stabilization. For example, if you test your engines 
using the same laboratory exhaust tubing for all tests, there would be 
no restrictions on the number of test hours that could be accumulated 
with the tubing, but it would need to be preconditioned separately for 
each engine.

[79 FR 23772, Apr. 28, 2014]



Sec. 1065.410  Maintenance limits for stabilized test engines.

    (a) After you stabilize the test engine's emission levels, you may 
do maintenance as allowed by the standard-setting part. However, you may 
not do any maintenance based on emission

[[Page 139]]

measurements from the test engine (i.e., unscheduled maintenance).
    (b) For any critical emission-related maintenance--other than what 
we specifically allow in the standard-setting part--you must completely 
test an engine for emissions before and after doing any maintenance that 
might affect emissions, unless we waive this requirement.
    (c) If you inspect an engine, keep a record of the inspection and 
update your application to document any changes that result. You may use 
any kind of equipment, instrument, or tool to identify bad engine 
components or perform maintenance if it is available at dealerships and 
other service outlets.
    (d) If we determine that a part failure, system malfunction, or 
associated repairs have made the engine's emission controls 
unrepresentative of production engines, you may no longer use it as an 
emission-data engine. Also, if your test engine has a major mechanical 
failure that requires you to take it apart, you may no longer use it as 
an emission-data engine.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37314, June 30, 2008; 
79 FR 23773, Apr. 28, 2014; 80 FR 9118, Feb. 19, 2015]



Sec. 1065.415  Durability demonstration.

    If the standard-setting part requires durability testing, you must 
accumulate service in a way that represents how you expect the engine to 
operate in use. You may accumulate service hours using an accelerated 
schedule, such as through continuous operation or by using duty cycles 
that are more aggressive than in-use operation, subject to any pre-
approval requirements established in the applicable standard-setting 
part.
    (a) Maintenance. The following limits apply to the maintenance that 
we allow you to do on an emission-data engine:
    (1) You may perform scheduled maintenance that you recommend to 
operators, but only if it is consistent with the standard-setting part's 
restrictions.
    (2) You may perform additional maintenance only as specified in 
Sec. 1065.410 or allowed by the standard-setting part.
    (b) Emission measurements. Perform emission tests following the 
provisions of the standard setting part and this part, as applicable. 
Perform emission tests to determine deterioration factors consistent 
with good engineering judgment. Evenly space any tests between the first 
and last test points throughout the durability period, unless we approve 
otherwise.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37315, June 30, 2008]



    Subpart F_Performing an Emission Test Over Specified Duty Cycles



Sec. 1065.501  Overview.

    (a) Use the procedures detailed in this subpart to measure engine 
emissions over a specified duty cycle. Refer to subpart J of this part 
for field test procedures that describe how to measure emissions during 
in-use engine operation. This section describes how to:
    (1) Map your engine, if applicable, by recording specified speed and 
torque data, as measured from the engine's primary output shaft.
    (2) Transform normalized duty cycles into reference duty cycles for 
your engine by using an engine map.
    (3) Prepare your engine, equipment, and measurement instruments for 
an emission test.
    (4) Perform pre-test procedures to verify proper operation of 
certain equipment and analyzers.
    (5) Record pre-test data.
    (6) Start or restart the engine and sampling systems.
    (7) Sample emissions throughout the duty cycle.
    (8) Record post-test data.
    (9) Perform post-test procedures to verify proper operation of 
certain equipment and analyzers.
    (10) Weigh PM samples.
    (b) Unless we specify otherwise, you may control the regeneration 
timing of infrequently regenerated aftertreatment devices such as diesel 
particulate filters using good engineering judgment. You may control the 
regeneration timing using a sequence of engine operating conditions or 
you may initiate regeneration with an external regeneration switch or 
other command. This provision also allows you to ensure that a 
regeneration

[[Page 140]]

event does not occur during an emission test.
    (c) An emission test generally consists of measuring emissions and 
other parameters while an engine follows one or more duty cycles that 
are specified in the standard-setting part. There are two general types 
of duty cycles:
    (1) Transient cycles. Transient duty cycles are typically specified 
in the standard-setting part as a second-by-second sequence of speed 
commands and normalized torque (or power) commands. Operate an engine 
over a transient cycle such that the speed and torque of the engine's 
primary output shaft follows the target values. Proportionally sample 
emissions and other parameters and use the calculations in subpart G of 
this part to calculate emissions. Start a transient test according to 
the standard-setting part, as follows:
    (i) A cold-start transient cycle where you start to measure 
emissions just before starting an engine that has not been warmed up.
    (ii) A hot-start transient cycle where you start to measure 
emissions just before starting a warmed-up engine.
    (iii) A hot running transient cycle where you start to measure 
emissions after an engine is started, warmed up, and running.
    (2) Steady-state cycles. Steady-state duty cycles are typically 
specified in the standard-setting part as a list of discrete operating 
points (modes or notches), where each operating point has one value of a 
normalized speed command and one value of a normalized torque (or power) 
command. Ramped-modal cycles for steady-state testing also list test 
times for each mode and transition times between modes where speed and 
torque are linearly ramped between modes, even for cycles with % power. 
Start a steady-state cycle as a hot running test, where you start to 
measure emissions after an engine is started, warmed up and running. Run 
a steady-state duty cycle as a discrete-mode cycle or a ramped-modal 
cycle, as follows:
    (i) Discrete-mode cycles. Before emission sampling, stabilize an 
engine at the first discrete mode of the duty cycle specified in the 
standard-setting part. Sample emissions and other parameters for that 
mode in the same manner as a transient cycle, with the exception that 
reference speed and torque values are constant. Record data for that 
mode, transition to the next mode, and then stabilize the engine at the 
next mode. Continue to sample each mode discretely as a separate test 
interval and calculate composite brake-specific emission results 
according to Sec. 1065.650(g)(2).
    (A) Use good engineering judgment to determine the time required to 
stabilize the engine. You may make this determination before starting 
the test based on prior experience, or you may make this determination 
in real time based an automated stability criteria. If needed, you may 
continue to operate the engine after reaching stability to get 
laboratory equipment ready for sampling.
    (B) Collect PM on separate PM sample media for each mode.
    (C) The minimum sample time is 60 seconds. We recommend that you 
sample both gaseous and PM emissions over the same test interval. If you 
sample gaseous and PM emissions over different test intervals, there 
must be no change in engine operation between the two test intervals. 
These two test intervals may completely or partially overlap, they may 
run consecutively, or they may be separated in time.
    (ii) Ramped-modal cycles. Perform ramped-modal cycles similar to the 
way you would perform transient cycles, except that ramped-modal cycles 
involve mostly steady-state engine operation. Generate a ramped-modal 
duty cycle as a sequence of second-by-second (1 Hz) reference speed and 
torque points. Run the ramped-modal duty cycle in the same manner as a 
transient cycle and use the 1 Hz reference speed and torque values to 
validate the cycle, even for cycles with % power. Proportionally sample 
emissions and other parameters during the cycle and use the calculations 
in subpart G of this part to calculate emissions.
    (d) Other subparts in this part identify how to select and prepare 
an engine for testing (subpart E), how to perform the required engine 
service accumulation (subpart E), and how to calculate emission results 
(subpart G).

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    (e) Subpart J of this part describes how to perform field testing.

[79 FR 23773, Apr. 28, 2014]



Sec. 1065.510  Engine mapping.

    (a) Applicability, scope, and frequency. An engine map is a data set 
that consists of a series of paired data points that represent the 
maximum brake torque versus engine speed, measured at the engine's 
primary output shaft. Map your engine if the standard-setting part 
requires engine mapping to generate a duty cycle for your engine 
configuration. Map your engine while it is connected to a dynamometer or 
other device that can absorb work output from the engine's primary 
output shaft according to Sec. 1065.110. To establish speed and torque 
values for mapping, we generally recommend that you stabilize an engine 
for at least 15 seconds at each setpoint and record the mean feedback 
speed and torque of the last (4 to 6) seconds. Configure any auxiliary 
work inputs and outputs such as hybrid, turbo-compounding, or 
thermoelectric systems to represent their in-use configurations, and use 
the same configuration for emission testing. See Figure 1 of Sec. 
1065.210. This may involve configuring initial states of charge and 
rates and times of auxiliary-work inputs and outputs. We recommend that 
you contact the Designated Compliance Officer before testing to 
determine how you should configure any auxiliary-work inputs and 
outputs. Use the most recent engine map to transform a normalized duty 
cycle from the standard-setting part to a reference duty cycle specific 
to your engine. Normalized duty cycles are specified in the standard-
setting part. You may update an engine map at any time by repeating the 
engine-mapping procedure. You must map or re-map an engine before a test 
if any of the following apply:
    (1) If you have not performed an initial engine map.
    (2) If the atmospheric pressure near the engine's air inlet is not 
within [5 kPa of the atmospheric pressure recorded at the time of the 
last engine map.
    (3) If the engine or emission-control system has undergone changes 
that might affect maximum torque performance. This includes changing the 
configuration of auxiliary work inputs and outputs.
    (4) If you capture an incomplete map on your first attempt or you do 
not complete a map within the specified time tolerance. You may repeat 
mapping as often as necessary to capture a complete map within the 
specified time.
    (b) Mapping variable-speed engines. Map variable-speed engines as 
follows:
    (1) Record the atmospheric pressure.
    (2) Warm up the engine by operating it. We recommend operating the 
engine at any speed and at approximately 75% of its expected maximum 
power. Continue the warm-up until the engine coolant, block, or head 
absolute temperature is within [2% of its mean value for at least 2 min 
or until the engine thermostat controls engine temperature.
    (3) Operate the engine at its warm idle speed as follows:
    (i) For engines with a low-speed governor, set the operator demand 
to minimum, use the dynamometer or other loading device to target a 
torque of zero on the engine's primary output shaft, and allow the 
engine to govern the speed. Measure this warm idle speed; we recommend 
recording at least 30 values of speed and using the mean of those 
values.
    (ii) For engines without a low-speed governor, operate the engine at 
warm idle speed and zero torque on the engine's primary output shaft. 
You may use the dynamometer to target a torque of zero on the engine's 
primary output shaft, and manipulate the operator demand to control the 
speed to target the manufacturer-declared value for the lowest engine 
speed possible with minimum load (also known as manufacturer-declared 
warm idle speed). You may alternatively use the dynamometer to target 
the manufacturer-declared warm idle speed and manipulate the operator 
demand to control the torque on the engine's primary output shaft to 
zero.
    (iii) For variable-speed engines with or without a low-speed 
governor, if a nonzero idle torque is representative of in-use 
operation, you may use the dynamometer or operator demand to target the 
manufacturer-declared idle torque instead of targeting zero torque

[[Page 142]]

as specified in paragraphs (b)(3)(i) and (ii) of this section. Control 
speed as specified in paragraph (b)(3)(i) or (ii) of this section, as 
applicable. If you use this option for engines with a low-speed governor 
to measure the warm idle speed with the manufacturer-declared torque at 
this step, you may use this as the warm-idle speed for cycle generation 
as specified in paragraph (b)(6) of this section. However, if you 
identify multiple warm idle torques under paragraph (f)(4)(i) of this 
section, measure the warm idle speed at only one torque level for this 
paragraph (b)(3).
    (4) Set operator demand to maximum and control engine speed at (95 
[1) % of its warm idle speed determined above for at least 15 seconds. 
For engines with reference duty cycles whose lowest speed is greater 
than warm idle speed, you may start the map at (95 [1) % of the lowest 
reference speed.
    (5) Perform one of the following:
    (i) For any engine subject only to steady-state duty cycles, you may 
perform an engine map by using discrete speeds. Select at least 20 
evenly spaced setpoints from 95% of warm idle speed to the highest speed 
above maximum power at which 50% of maximum power occurs. We refer to 
this 50% speed as the check point speed as described in paragraph 
(b)(5)(iii) of this section. At each setpoint, stabilize speed and allow 
torque to stabilize. Record the mean speed and torque at each setpoint. 
Use linear interpolation to determine intermediate speeds and torques. 
Use this series of speeds and torques to generate the power map as 
described in paragraph (e) of this section.
    (ii) For any variable-speed engine, you may perform an engine map by 
using a continuous sweep of speed by continuing to record the mean 
feedback speed and torque at 1 Hz or more frequently and increasing 
speed at a constant rate such that it takes (4 to 6) min to sweep from 
95% of warm idle speed to the check point speed as described in 
paragraph (b)(5)(iii) of this section. Use good engineering judgment to 
determine when to stop recording data to ensure that the sweep is 
complete. In most cases, this means that you can stop the sweep at any 
point after the power falls to 50% of the maximum value. From the series 
of mean speed and maximum torque values, use linear interpolation to 
determine intermediate values. Use this series of speeds and torques to 
generate the power map as described in paragraph (e) of this section.
    (iii) The check point speed of the map is the highest speed above 
maximum power at which 50% of maximum power occurs. If this speed is 
unsafe or unachievable (e.g., for ungoverned engines or engines that do 
not operate at that point), use good engineering judgment to map up to 
the maximum safe speed or maximum achievable speed. For discrete 
mapping, if the engine cannot be mapped to the check point speed, make 
sure the map includes at least 20 points from 95% of warm idle to the 
maximum mapped speed. For continuous mapping, if the engine cannot be 
mapped to the check point speed, verify that the sweep time from 95% of 
warm idle to the maximum mapped speed is (4 to 6) min.
    (iv) Note that under Sec. 1065.10(c)(1) we may allow you to 
disregard portions of the map when selecting maximum test speed if the 
specified procedure would result in a duty cycle that does not represent 
in-use operation.
    (6) Use one of the following methods to determine warm high-idle 
speed for engines with a high-speed governor if they are subject to 
transient testing with a duty cycle that includes reference speed values 
above 100%:
    (i) You may use a manufacturer-declared warm high-idle speed if the 
engine is electronically governed. For engines with a high-speed 
governor that shuts off torque output at a manufacturer-specified speed 
and reactivates at a lower manufacturer-specified speed (such as engines 
that use ignition cut-off for governing), declare the middle of the 
specified speed range as the warm high-idle speed.
    (ii) Measure the warm high-idle speed using the following procedure:
    (A) Set operator demand to maximum and use the dynamometer to target 
zero torque on the engine's primary output shaft. If the mean feedback 
torque is within [1% of Tmax mapped, you may use the observed 
mean feedback speed at that point as the measured warm high-idle speed.

[[Page 143]]

    (B) If the engine is unstable as a result of in-use production 
components (such as engines that use ignition cut-off for governing, as 
opposed to unstable dynamometer operation), you must use the mean 
feedback speed from paragraph (b)(6)(ii)(A) of this section as the 
measured warm high-idle speed. The engine is considered unstable if any 
of the 1 Hz speed feedback values are not within [2% of the calculated 
mean feedback speed. We recommend that you determine the mean as the 
value representing the midpoint between the observed maximum and minimum 
recorded feedback speed.
    (C) If your dynamometer is not capable of achieving a mean feedback 
torque within [1% of Tmax mapped, operate the engine at a 
second point with operator demand set to maximum with the dynamometer 
set to target a torque equal to the recorded mean feedback torque on the 
previous point plus 20% of Tmax mapped. Use this data point 
and the data point from paragraph (b)(6)(ii)(A) of this section to 
extrapolate the engine speed where torque is equal to zero.
    (D) You may use a manufacturer-declared Tmax instead of 
the measured Tmax mapped. If you do this, or if you are able 
to determine mean feedback speed as described in paragraphs 
(b)(6)(ii)(A) and (B) of this section, you may measure the warm high-
idle speed before running the speed sweep specified in paragraph (b)(5) 
of this section.
    (7) For engines with a low-speed governor, if a nonzero idle torque 
is representative of in-use operation, operate the engine at warm idle 
with the manufacturer-declared idle torque. Set the operator demand to 
minimum, use the dynamometer to target the declared idle torque, and 
allow the engine to govern the speed. Measure this speed and use it as 
the warm idle speed for cycle generation in Sec. 1065.512. We recommend 
recording at least 30 values of speed and using the mean of those 
values. If you identify multiple warm idle torques under paragraph 
(f)(4)(i) of this section, measure the warm idle speed at each torque. 
You may map the idle governor at multiple load levels and use this map 
to determine the measured warm idle speed at the declared idle 
torque(s).
    (c) Negative torque mapping. If your engine is subject to a 
reference duty cycle that specifies negative torque values (i.e., engine 
motoring), generate a motoring torque curve by any of the following 
procedures:
    (1) Multiply the positive torques from your map by -40%. Use linear 
interpolation to determine intermediate values.
    (2) Map the amount of negative torque required to motor the engine 
by repeating paragraph (b) of this section with minimum operator demand. 
You may start the negative torque map at either the minimum or maximum 
speed from paragraph (b) of this section.
    (3) Determine the amount of negative torque required to motor the 
engine at the following two points near the ends of the engine's speed 
range. Operate the engine at these two points at minimum operator 
demand. Use linear interpolation to determine intermediate values.
    (i) Low-speed point. For engines without a low-speed governor, 
determine the amount of negative torque at warm idle speed. For engines 
with a low-speed governor, motor the engine above warm idle speed so the 
governor is inactive and determine the amount of negative torque at that 
speed.
    (ii) High-speed point. For engines without a high-speed governor, 
determine the amount of negative torque at the maximum safe speed or the 
maximum representative speed. For engines with a high-speed governor, 
determine the amount of negative torque at a speed at or above 
nhi per Sec. 1065.610(c)(2).
    (4) For engines with an electric hybrid system, map the negative 
torque required to motor the engine and absorb any power delivered from 
the RESS by repeating paragraph (g)(2) of this section with minimum 
operator demand, stopping the sweep to discharge the RESS when the 
absolute instantaneous power measured from the RESS drops below the 
expected maximum absolute power from the RESS by more than 2% of total 
system maximum power (including engine motoring and RESS power) as 
determined from mapping the negative torque.

[[Page 144]]

    (d) Mapping constant-speed engines. For constant-speed engines, 
generate a map as follows:
    (1) Record the atmospheric pressure.
    (2) Warm up the engine by operating it. We recommend operating the 
engine at approximately 75% of the engine's expected maximum power. 
Continue the warm-up until the engine coolant, block, or head absolute 
temperature is within [2% of its mean value for at least 2 min or until 
the engine thermostat controls engine temperature.
    (3) You may operate the engine with a production constant-speed 
governor or simulate a constant-speed governor by controlling engine 
speed with an operator demand control system described in Sec. 
1065.110. Use either isochronous or speed-droop governor operation, as 
appropriate.
    (4) With the governor or simulated governor controlling speed using 
operator demand, operate the engine at no-load governed speed (at high 
speed, not low idle) for at least 15 seconds.
    (5) Record at 1 Hz the mean of feedback speed and torque. Use the 
dynamometer to increase torque at a constant rate. Unless the standard-
setting part specifies otherwise, complete the map such that it takes (2 
to 4) min to sweep from no-load governed speed to the speed below 
maximum mapped power at which the engine develops 90% of maximum mapped 
power. You may map your engine to lower speeds. Stop recording after you 
complete the sweep. Use this series of speeds and torques to generate 
the power map as described in paragraph (e) of this section.
    (i) For constant-speed engines subject only to steady-state testing, 
you may perform an engine map by using a series of discrete torques. 
Select at least five evenly spaced torque setpoints from no-load to 80% 
of the manufacturer-declared test torque or to a torque derived from 
your published maximum power level if the declared test torque is 
unavailable. Starting at the 80% torque point, select setpoints in 2.5% 
or smaller intervals, stopping at the endpoint torque. The endpoint 
torque is defined as the first discrete mapped torque value greater than 
the torque at maximum observed power where the engine outputs 90% of the 
maximum observed power; or the torque when engine stall has been 
determined using good engineering judgment (i.e. sudden deceleration of 
engine speed while adding torque). You may continue mapping at higher 
torque setpoints. At each setpoint, allow torque and speed to stabilize. 
Record the mean feedback speed and torque at each setpoint. From this 
series of mean feedback speed and torque values, use linear 
interpolation to determine intermediate values. Use this series of mean 
feedback speeds and torques to generate the power map as described in 
paragraph (e) of this section.
    (ii) For any constant-speed engine, you may perform an engine map 
with a continuous torque sweep by continuing to record the mean feedback 
speed and torque at 1 Hz or more frequently. Use the dynamometer to 
increase torque. Increase the reference torque at a constant rate from 
no-load to the endpoint torque as defined in paragraph (d)(5)(i) of this 
section. You may continue mapping at higher torque setpoints. Unless the 
standard-setting part specifies otherwise, target a torque sweep rate 
equal to the manufacturer-declared test torque (or a torque derived from 
your published power level if the declared test torque is not known) 
divided by 180 seconds. Stop recording after you complete the sweep. 
Verify that the average torque sweep rate over the entire map is within 
[7% of the target torque sweep rate. Use linear interpolation to 
determine intermediate values from this series of mean feedback speed 
and torque values. Use this series of mean feedback speeds and torques 
to generate the power map as described in paragraph (e) of this section.
    (iii) For any isochronous governed (0% speed droop) constant-speed 
engine, you may map the engine with two points as described in this 
paragraph (d)(5)(iii). After stabilizing at the no-load governed speed 
in paragraph (d)(4) of this section, record the mean feedback speed and 
torque. Continue to operate the engine with the governor or simulated 
governor controlling engine speed using operator demand, and control the 
dynamometer to target a speed of 99.5% of the recorded mean no-load 
governed speed. Allow speed and torque

[[Page 145]]

to stabilize. Record the mean feedback speed and torque. Record the 
target speed. The absolute value of the speed error (the mean feedback 
speed minus the target speed) must be no greater than 0.1% of the 
recorded mean no-load governed speed. From this series of two mean 
feedback speed and torque values, use linear interpolation to determine 
intermediate values. Use this series of two mean feedback speeds and 
torques to generate a power map as described in paragraph (e) of this 
section. Note that the measured maximum test torque as determined in 
Sec. 1065.610 (b)(1) will be the mean feedback torque recorded on the 
second point.
    (e) Power mapping. For all engines, create a power-versus-speed map 
by transforming torque and speed values to corresponding power values. 
Use the mean values from the recorded map data. Do not use any 
interpolated values. Multiply each torque by its corresponding speed and 
apply the appropriate conversion factors to arrive at units of power 
(kW). Interpolate intermediate power values between these power values, 
which were calculated from the recorded map data.
    (f) Measured and declared test speeds and torques. You must select 
test speeds and torques for cycle generation as required in this 
paragraph (f). ``Measured'' values are either directly measured during 
the engine mapping process or they are determined from the engine map. 
``Declared'' values are specified by the manufacturer. When both 
measured and declared values are available, you may use declared test 
speeds and torques instead of measured speeds and torques if they meet 
the criteria in this paragraph (f). Otherwise, you must use measured 
speeds and torques derived from the engine map.
    (1) Measured speeds and torques. Determine the applicable speeds and 
torques for the duty cycles you will run:
    (i) Measured maximum test speed for variable-speed engines according 
to Sec. 1065.610.
    (ii) Measured maximum test torque for constant-speed engines 
according to Sec. 1065.610.
    (iii) Measured ``A'', ``B'', and ``C'' speeds for variable-speed 
engines according to Sec. 1065.610.
    (iv) Measured intermediate speed for variable-speed engines 
according to Sec. 1065.610.
    (v) For variable-speed engines with a low-speed governor, measure 
warm idle speed according to Sec. 1065.510(b) and use this speed for 
cycle generation in Sec. 1065.512. For engines with no low-speed 
governor, instead use the manufacturer-declared warm idle speed.
    (2) Required declared speeds. You must declare the lowest engine 
speed possible with minimum load (i.e., manufacturer-declared warm idle 
speed). This is applicable only to variable-speed engines with no low-
speed governor. For engines with no low-speed governor, the declared 
warm idle speed is used for cycle generation in Sec. 1065.512. Declare 
this speed in a way that is representative of in-use operation. For 
example, if your engine is typically connected to an automatic 
transmission or a hydrostatic transmission, declare this speed at the 
idle speed at which your engine operates when the transmission is 
engaged.
    (3) Optional declared speeds. You may use declared speeds instead of 
measured speeds as follows:
    (i) You may use a declared value for maximum test speed for 
variable-speed engines if it is within (97.5 to 102.5) % of the 
corresponding measured value. You may use a higher declared speed if the 
length of the ``vector'' at the declared speed is within 2% of the 
length of the ``vector'' at the measured value. The term vector refers 
to the square root of the sum of normalized engine speed squared and the 
normalized full-load power (at that speed) squared, consistent with the 
calculations in Sec. 1065.610.
    (ii) You may use a declared value for intermediate, ``A'', ``B'', or 
``C'' speeds for steady-state tests if the declared value is within 
(97.5 to 102.5)% of the corresponding measured value.
    (iii) For electronically governed engines, you may use a declared 
warm high-idle speed for calculating the alternate maximum test speed as 
specified in Sec. 1065.610.
    (4) Required declared torques. If a nonzero idle or minimum torque 
is representative of in-use operation, you must declare the appropriate 
torque as follows:

[[Page 146]]

    (i) For variable-speed engines, declare a warm idle torque that is 
representative of in-use operation. For example, if your engine is 
typically connected to an automatic transmission or a hydrostatic 
transmission, declare the torque that occurs at the idle speed at which 
your engine operates when the transmission is engaged. Use this value 
for cycle generation. You may use multiple warm idle torques and 
associated idle speeds in cycle generation for representative testing. 
For example, for cycles that start the engine and begin with idle, you 
may start a cycle in idle with the transmission in neutral with zero 
torque and later switch to a different idle with the transmission in 
drive with the Curb-Idle Transmission Torque (CITT). For variable-speed 
engines intended primarily for propulsion of a vehicle with an automatic 
transmission where that engine is subject to a transient duty cycle with 
idle operation, you must declare a CITT. You must specify a CITT based 
on typical applications at the mean of the range of idle speeds you 
specify at stabilized temperature conditions.
    (ii) For constant-speed engines, declare a warm minimum torque that 
is representative of in-use operation. For example, if your engine is 
typically connected to a machine that does not operate below a certain 
minimum torque, declare this torque and use it for cycle generation.
    (5) Optional declared torques. (i) For variable-speed engines you 
may declare a maximum torque over the engine operating range. You may 
use the declared value for measuring warm high-idle speed as specified 
in this section.
    (ii) For constant-speed engines you may declare a maximum test 
torque. You may use the declared value for cycle generation if it is 
within (95 to 100) % of the measured value.
    (g) Mapping variable-speed engines with an electric hybrid system. 
Map variable-speed engines that include electric hybrid systems as 
described in this paragraph (g). You may ask to apply these provisions 
to other types of hybrid engines, consistent with good engineering 
judgment. However, do not use this procedure for engines used in hybrid 
vehicles where the hybrid system is certified as part of the vehicle 
rather than the engine. Follow the steps for mapping a variable-speed 
engine as given in paragraph (b)(5) of this section except as noted in 
this paragraph (g). You must generate one engine map with the hybrid 
system inactive as described in paragraph (g)(1) of this section, and a 
separate map with the hybrid system active as described in paragraph 
(g)(2) of this section. See the standard-setting part to determine how 
to use these maps. The map with the system inactive is typically used to 
generate steady-state duty cycles, but may also be used to generate 
transient cycles, such as those that do not involve engine motoring. 
This hybrid-inactive map is also used for generating the hybrid-active 
map. The hybrid-active map is typically used to generate transient duty 
cycles that involve engine motoring.
    (1) Prepare the engine for mapping by either deactivating the hybrid 
system or by operating the engine as specified in paragraph (b)(4) of 
this section and remaining at this condition until the rechargeable 
energy storage system (RESS) is depleted. Once the hybrid has been 
disabled or the RESS is depleted, perform an engine map as specified in 
paragraph (b)(5) of this section. If the RESS was depleted instead of 
deactivated, ensure that instantaneous power from the RESS remains less 
than 2% of the instantaneous measured power from the engine (or engine-
hybrid system) at all engine speeds.
    (2) The purpose of the mapping procedure in this paragraph (g) is to 
determine the maximum torque available at each speed, such as what might 
occur during transient operation with a fully charged RESS. Use one of 
the following methods to generate a hybrid-active map:
    (i) Perform an engine map by using a series of continuous sweeps to 
cover the engine's full range of operating speeds. Prepare the engine 
for hybrid-active mapping by ensuring that the RESS state of charge is 
representative of normal operation. Perform the sweep as specified in 
paragraph (b)(5)(ii) of this section, but stop the sweep to charge the 
RESS when the power measured from the RESS drops below the expected 
maximum power from the RESS by more than 2% of

[[Page 147]]

total system power (including engine and RESS power). Unless good 
engineering judgment indicates otherwise, assume that the expected 
maximum power from the RESS is equal to the measured RESS power at the 
start of the sweep segment. For example, if the 3-second rolling average 
of total engine-RESS power is 200 kW and the power from the RESS at the 
beginning of the sweep segment is 50 kW, once the power from the RESS 
reaches 46 kW, stop the sweep to charge the RESS. Note that this 
assumption is not valid where the hybrid motor is torque-limited. 
Calculate total system power as a 3-second rolling average of 
instantaneous total system power. After each charging event, stabilize 
the engine for 15 seconds at the speed at which you ended the previous 
segment with operator demand set to maximum before continuing the sweep 
from that speed. Repeat the cycle of charging, mapping, and recharging 
until you have completed the engine map. You may shut down the system or 
include other operation between segments to be consistent with the 
intent of this paragraph (g)(2)(i). For example, for systems in which 
continuous charging and discharging can overheat batteries to an extent 
that affects performance, you may operate the engine at zero power from 
the RESS for enough time after the system is recharged to allow the 
batteries to cool. Use good engineering judgment to smooth the torque 
curve to eliminate discontinuities between map intervals.
    (ii) Perform an engine map by using discrete speeds. Select map 
setpoints at intervals defined by the ranges of engine speed being 
mapped. From 95% of warm idle speed to 90% of the expected maximum test 
speed, select setpoints that result in a minimum of 13 equally spaced 
speed setpoints. From 90% to 110% of expected maximum test speed, select 
setpoints in equally spaced intervals that are nominally 2% of expected 
maximum test speed. Above 110% of expected maximum test speed, select 
setpoints based on the same speed intervals used for mapping from 95% 
warm idle speed to 90% maximum test speed. You may stop mapping at the 
highest speed above maximum power at which 50% of maximum power occurs. 
We refer to the speed at 50% power as the check point speed as described 
in paragraph (b)(5)(iii) of this section. Stabilize engine speed at each 
setpoint, targeting a torque value at 70% of peak torque at that speed 
without hybrid-assist. Make sure the engine is fully warmed up and the 
RESS state of charge is within the normal operating range. Snap the 
operator demand to maximum, operate the engine there for at least 10 
seconds, and record the 3-second rolling average feedback speed and 
torque at 1 Hz or higher. Record the peak 3-second average torque and 3-
second average speed at that point. Use linear interpolation to 
determine intermediate speeds and torques. Follow Sec. 1065.610(a) to 
calculate the maximum test speed. Verify that the measured maximum test 
speed falls in the range from 92 to 108% of the estimated maximum test 
speed. If the measured maximum test speed does not fall in this range, 
rerun the map using the measured value of maximum test speed.
    (h) Other mapping procedures. You may use other mapping procedures 
if you believe the procedures specified in this section are unsafe or 
unrepresentative for your engine. Any alternate techniques you use must 
satisfy the intent of the specified mapping procedures, which is to 
determine the maximum available torque at all engine speeds that occur 
during a duty cycle. Identify any deviations from this section's mapping 
procedures when you submit data to us.

[73 FR 37315, June 30, 2008, as amended at 73 FR 59330, Oct. 8, 2008; 75 
FR 23042, Apr. 30, 2010; 76 FR 57448, Sept. 15, 2011; 79 FR 23773, Apr. 
28, 2014; 81 FR 74169, Oct. 25, 2016]



Sec. 1065.512  Duty cycle generation.

    (a) Generate duty cycles according to this section if the standard-
setting part requires engine mapping to generate a duty cycle for your 
engine configuration. The standard-setting part generally defines 
applicable duty cycles in a normalized format. A normalized duty cycle 
consists of a sequence of paired values for speed and torque or for 
speed and power.
    (b) Transform normalized values of speed, torque, and power using 
the following conventions:

[[Page 148]]

    (1) Engine speed for variable-speed engines. For variable-speed 
engines, normalized speed may be expressed as a percentage between warm 
idle speed, fnidle, and maximum test speed, 
fntest, or speed may be expressed by referring to a defined 
speed by name, such as ``warm idle,'' ``intermediate speed,'' or ``A,'' 
``B,'' or ``C'' speed. Section 1065.610 describes how to transform these 
normalized values into a sequence of reference speeds, fnref. 
Running duty cycles with negative or small normalized speed values near 
warm idle speed may cause low-speed idle governors to activate and the 
engine torque to exceed the reference torque even though the operator 
demand is at a minimum. In such cases, we recommend controlling the 
dynamometer so it gives priority to follow the reference torque instead 
of the reference speed and let the engine govern the speed. Note that 
the cycle-validation criteria in Sec. 1065.514 allow an engine to 
govern itself. This allowance permits you to test engines with enhanced-
idle devices and to simulate the effects of transmissions such as 
automatic transmissions. For example, an enhanced-idle device might be 
an idle speed value that is normally commanded only under cold-start 
conditions to quickly warm up the engine and aftertreatment devices. In 
this case, negative and very low normalized speeds will generate 
reference speeds below this higher enhanced idle speed and we recommend 
controlling the dynamometer so it gives priority to follow the reference 
torque, controlling the operator demand so it gives priority to follow 
reference speed and let the engine govern the speed when the operator 
demand is at minimum.
    (2) Engine torque for variable-speed engines. For variable-speed 
engines, normalized torque is expressed as a percentage of the mapped 
torque at the corresponding reference speed. Section 1065.610 describes 
how to transform normalized torques into a sequence of reference 
torques, Tref. Section 1065.610 also describes special 
requirements for modifying transient duty cycles for variable-speed 
engines intended primarily for propulsion of a vehicle with an automatic 
transmission. Section 1065.610 also describes under what conditions you 
may command Tref greater than the reference torque you 
calculated from a normalized duty cycle. This provision permits you to 
command Tref values that are limited by a declared minimum 
torque. For any negative torque commands, command minimum operator 
demand and use the dynamometer to control engine speed to the reference 
speed, but if reference speed is so low that the idle governor 
activates, we recommend using the dynamometer to control torque to zero, 
CITT, or a declared minimum torque as appropriate. Note that you may 
omit power and torque points during motoring from the cycle-validation 
criteria in Sec. 1065.514. Also, use the maximum mapped torque at the 
minimum mapped speed as the maximum torque for any reference speed at or 
below the minimum mapped speed.
    (3) Engine torque for constant-speed engines. For constant-speed 
engines, normalized torque is expressed as a percentage of maximum test 
torque, Ttest. Section 1065.610 describes how to transform 
normalized torques into a sequence of reference torques, 
Tref. Section 1065.610 also describes under what conditions 
you may command Tref greater than the reference torque you 
calculated from the normalized duty cycle. This provision permits you to 
command Tref values that are limited by a declared minimum 
torque.
    (4) Engine power. For all engines, normalized power is expressed as 
a percentage of mapped power at maximum test speed, fntest, 
unless otherwise specified by the standard-setting part. Section 
1065.610 describes how to transform these normalized values into a 
sequence of reference powers, Pref. Convert these reference 
powers to corresponding torques for operator demand and dynamometer 
control. Use the reference speed associated with each reference power 
point for this conversion. As with cycles specified with % torque, issue 
torque commands more frequently and linearly interpolate between these 
reference torque values generated from cycles with % power.
    (5) Ramped-modal cycles. For ramped-modal cycles, generate reference 
speed and torque values at 1 Hz and use this sequence of points to run 
the cycle and validate it in the same manner as with

[[Page 149]]

a transient cycle. During the transition between modes, linearly ramp 
the denormalized reference speed and torque values between modes to 
generate reference points at 1 Hz. Do not linearly ramp the normalized 
reference torque values between modes and then denormalize them. Do not 
linearly ramp normalized or denormalized reference power points. These 
cases will produce nonlinear torque ramps in the denormalized reference 
torques. If the speed and torque ramp runs through a point above the 
engine's torque curve, continue to command the reference torques and 
allow the operator demand to go to maximum. Note that you may omit power 
and either torque or speed points from the cycle-validation criteria 
under these conditions as specified in Sec. 1065.514.
    (c) For variable-speed engines, command reference speeds and torques 
sequentially to perform a duty cycle. Issue speed and torque commands at 
a frequency of at least 5 Hz for transient cycles and at least 1 Hz for 
steady-state cycles (i.e., discrete-mode and ramped-modal). Linearly 
interpolate between the 1 Hz reference values specified in the standard-
setting part to determine more frequently issued reference speeds and 
torques. During an emission test, record the feedback speeds and torques 
at a frequency of at least 5 Hz for transient cycles and at least 1 Hz 
for steady-state cycles. For transient cycles, you may record the 
feedback speeds and torques at lower frequencies (as low as 1 Hz) if you 
record the average value over the time interval between recorded values. 
Calculate the average values based on feedback values updated at a 
frequency of at least 5 Hz. Use these recorded values to calculate 
cycle-validation statistics and total work.
    (d) For constant-speed engines, operate the engine with the same 
production governor you used to map the engine in Sec. 1065.510 or 
simulate the in-use operation of a governor the same way you simulated 
it to map the engine in Sec. 1065.510. Command reference torque values 
sequentially to perform a duty cycle. Issue torque commands at a 
frequency of at least 5 Hz for transient cycles and at least 1 Hz for 
steady-state cycles (i.e., discrete-mode, ramped-modal). Linearly 
interpolate between the 1 Hz reference values specified in the standard-
setting part to determine more frequently issued reference torque 
values. During an emission test, record the feedback speeds and torques 
at a frequency of at least 5 Hz for transient cycles and at least 1 Hz 
for steady-state cycles. For transient cycles, you may record the 
feedback speeds and torques at lower frequencies (as low as 1 Hz) if you 
record the average value over the time interval between recorded values. 
Calculate the average values based on feedback values updated at a 
frequency of at least 5 Hz. Use these recorded values to calculate 
cycle-validation statistics and total work.
    (e) You may perform practice duty cycles with the test engine to 
optimize operator demand and dynamometer controls to meet the cycle-
validation criteria specified in Sec. 1065.514.

[73 FR 37317, June 30, 2008, as amended at 79 FR 23774, Apr. 28, 2014]



Sec. 1065.514  Cycle-validation criteria for operation over specified
duty cycles.

    Validate the execution of your duty cycle according to this section 
unless the standard-setting part specifies otherwise. This section 
describes how to determine if the engine's operation during the test 
adequately matched the reference duty cycle. This section applies only 
to speed, torque, and power from the engine's primary output shaft. 
Other work inputs and outputs are not subject to cycle-validation 
criteria. You must compare the original reference duty cycle points 
generated as described in Sec. 1065.512 to the corresponding feedback 
values recorded during the test. You may compare reference duty cycle 
points recorded during the test to the corresponding feedback values 
recorded during the test as long as the recorded reference values match 
the original points generated in Sec. 1065.512. The number of points in 
the validation regression are based on the number of points in the 
original reference duty cycle generated in Sec. 1065.512. For example 
if the original cycle has 1199 reference points at 1 Hz, then the 
regression will have up to 1199 pairs of reference and feedback values

[[Page 150]]

at the corresponding moments in the test. The feedback speed and torque 
signals may be filtered--either in real-time while the test is run or 
afterward in the analysis program. Any filtering that is used on the 
feedback signals used for cycle validation must also be used for 
calculating work. Feedback signals for control loops may use different 
filtering.
    (a) Testing performed by EPA. Our tests must meet the specifications 
of paragraph (f) of this section, unless we determine that failing to 
meet the specifications is related to engine performance rather than to 
shortcomings of the dynamometer or other laboratory equipment.
    (b) Testing performed by manufacturers. Emission tests that meet the 
specifications of paragraph (f) of this section satisfy the standard-
setting part's requirements for duty cycles. You may ask to use a 
dynamometer or other laboratory equipment that cannot meet those 
specifications. We will approve your request as long as using the 
alternate equipment does not adversely affect your ability to show 
compliance with the applicable emission standards.
    (c) Time-alignment. Because time lag between feedback values and the 
reference values may bias cycle-validation results, you may advance or 
delay the entire sequence of feedback engine speed and torque pairs to 
synchronize them with the reference sequence. If you advance or delay 
feedback signals for cycle validation, you must make the same adjustment 
for calculating work. You may use linear interpolation between 
successive recorded feedback signals to time shift an amount that is a 
fraction of the recording period.
    (d) Omitting additional points. Besides engine cranking, you may 
omit additional points from cycle-validation statistics as described in 
the following table:

   Table 1 of Sec. 1065.514--Permissible Criteria for Omitting Points From Duty-Cycle Regression Statistics
----------------------------------------------------------------------------------------------------------------
  When operator demand is at its . . .         you may omit . . .                       if . . .
----------------------------------------------------------------------------------------------------------------
             For reference duty cycles that are specified in terms of speed and torque (fnref, Tref)
----------------------------------------------------------------------------------------------------------------
minimum.................................  power and torque...........  Tref <0% (motoring).
minimum.................................  power and speed............  fnref = 0% (idle speed) and Tref = 0%
                                                                        (idle torque) and Tref - (2% [middot]
                                                                        Tmax mapped) fnref or T >Tref but not if fn
                                           speed.                       >(fnref [middot] 102%) and T >Tref [ (2%
                                                                        [middot] Tmax mapped).
maximum.................................  power and either torque or   fn fnref or P >Pref but not if fn
                                           speed.                       >(fnref [middot] 102%) and P >Pref + (2%
                                                                        [middot] Pmax mapped).
maximum.................................  power and either torque or   fn 1fn, feedback torque, 
a1T, and feedback power a1P.
    (2) Intercepts for feedback speed, a0fn, feedback torque, 
a0T, and feedback power a0P.
    (3) Standard estimates of error for feedback speed, 
SEEfn, feedback torque, SEET, and feedback power 
SEEP.

[[Page 151]]

    (4) Coefficients of determination for feedback speed, 
r\2\fn, feedback torque, r\2\T, and feedback power 
r\2\P.
    (f) Cycle-validation criteria. Unless the standard-setting part 
specifies otherwise, use the following criteria to validate a duty 
cycle:
    (1) For variable-speed engines, apply all the statistical criteria 
in Table 2 of this section.
    (2) For constant-speed engines, apply only the statistical criteria 
for torque in Table 2 of this section.
    (3) For discrete-mode steady-state testing, apply cycle-validation 
criteria by treating the sampling periods from the series of test modes 
as a continuous sampling period, analogous to ramped-modal testing and 
apply statistical criteria as described in paragraph (f)(1) or (f)(2) of 
this section. Note that if the gaseous and particulate test intervals 
are different periods of time, separate validations are required for the 
gaseous and particulate test intervals. Table 2 follows:

               Table 2 of Sec. 1065.514--Default Statistical Criteria for Validating Duty Cycles
----------------------------------------------------------------------------------------------------------------
              Parameter                         Speed                    Torque                   Power
----------------------------------------------------------------------------------------------------------------
Slope, a1............................  0.950 <=a1 <=1.030.....  0.830 <=a1 <=1.030.....  0.830 <=a1 <=1.030.
Absolute value of intercept, |  <=10% of warm idle.....  <=2% of maximum mapped   <=2% of maximum mapped
 a0|.                                                     torque.                  power.
Standard error of estimate, SEE......  <=5% of maximum test     <=10% of maximum mapped  <=10% of maximum mapped
                                        speed.                   torque.                  power.
Coefficient of determination, r2.....  >=0.970................  >=0.850................  >=0.910.
----------------------------------------------------------------------------------------------------------------


[73 FR 37318, June 30, 2008, as amended at 73 FR 59330, Oct. 8, 2008; 75 
FR 23042, Apr. 30, 2010; 76 FR 57450, Sept. 15, 2011]



Sec. 1065.516  Sample system decontamination and preconditioning.

    This section describes how to manage the impact of sampling system 
contamination on emission measurements. Use good engineering judgment to 
determine if you should decontaminate and precondition your sampling 
system. Contamination occurs when a regulated pollutant accumulates in 
the sample system in a high enough concentration to cause release during 
emission tests. Hydrocarbons and PM are generally the only regulated 
pollutants that contaminate sample systems. Note that although this 
section focuses on avoiding excessive contamination of sampling systems, 
you must also use good engineering judgment to avoid loss of sample to a 
sampling system that is too clean. The goal of decontamination is not to 
perfectly clean the sampling system, but rather to achieve equilibrium 
between the sampling system and the exhaust so emission components are 
neither lost to nor entrained from the sampling system.
    (a) You may perform contamination checks as follows to determine if 
decontamination is needed:
    (1) For dilute exhaust sampling systems, measure hydrocarbon and PM 
emissions by sampling with the CVS dilution air turned on, without an 
engine connected to it.
    (2) For raw analyzers and systems that collect PM samples from raw 
exhaust, measure hydrocarbon and PM emissions by sampling purified air 
or nitrogen.
    (3) When calculating zero emission levels, apply all applicable 
corrections, including initial THC contamination and diluted (CVS) 
exhaust background corrections.
    (4) Sampling systems are considered contaminated if either of the 
following conditions applies:
    (i) The hydrocarbon emission level exceeds 2% of the flow-weighted 
mean concentration expected at the HC standard.
    (ii) The PM emission level exceeds 5% of the level expected at the 
standard and exceeds 20 [micro] g on a 47 mm PTFE membrane filter.
    (b) To precondition or decontaminate sampling systems, use the 
following recommended procedure or select a different procedure using 
good engineering judgment:
    (1) Start the engine and use good engineering judgment to operate it 
at a condition that generates high exhaust

[[Page 152]]

temperatures at the sample probe inlet.
    (2) Operate any dilution systems at their expected flow rates. 
Prevent aqueous condensation in the dilution systems.
    (3) Operate any PM sampling systems at their expected flow rates.
    (4) Sample PM for at least 10 min using any sample media. You may 
change sample media at any time during this process and you may discard 
them without weighing them.
    (5) You may purge any gaseous sampling systems that do not require 
decontamination during this procedure.
    (6) You may conduct calibrations or verifications on any idle 
equipment or analyzers during this procedure.
    (c) If your sampling system is still contaminated following the 
procedures specified in paragraph (b) of this section, you may use more 
aggressive procedures to decontaminate the sampling system, as long as 
the decontamination does not cause the sampling system to be cleaner 
than an equilibrium condition such that artificially low emission 
measurements may result.

[79 FR 23774, Apr. 28, 2014]



Sec. 1065.518  Engine preconditioning.

    (a) This section applies for engines where measured emissions are 
affected by prior operation, such as with a diesel engine that relies on 
urea-based selective catalytic reduction. Note that Sec. 1065.520(e) 
allows you to run practice duty cycles before the emission test; this 
section recommends how to do this for the purpose of preconditioning the 
engine. Follow the standard-setting part if it specifies a different 
engine preconditioning procedure.
    (b) The intent of engine preconditioning is to manage the 
representativeness of emissions and emission controls over the duty 
cycle and to reduce bias.
    (c) This paragraph (c) specifies the engine preconditioning 
procedures for different types of duty cycles. You must identify the 
amount of preconditioning before starting to precondition. You must run 
the predefined amount of preconditioning. You may measure emissions 
during preconditioning. You may not abort an emission test sequence 
based on emissions measured during preconditioning. For confirmatory 
testing, you may ask us to run more preconditioning cycles than we 
specify in this paragraph (c); we will agree to this only if you show 
that additional preconditioning cycles are required to meet the intent 
of paragraph (b) of this section, for example, due to the effect of DPF 
regeneration on NH3 storage in the SCR catalyst. Perform 
preconditioning as follows, noting that the specific cycles for 
preconditioning are the same ones that apply for emission testing:
    (1) Cold-start transient cycle. Precondition the engine by running 
at least one hot-start transient cycle. We will precondition your engine 
by running two hot-start transient cycles. Immediately after completing 
each preconditioning cycle, shut down the engine and complete the 
engine-off soak period. Immediately after completing the last 
preconditioning cycle, shut down the engine and begin the cold soak as 
described in Sec. 1065.530(a)(1).
    (2) Hot-start transient cycle. Precondition the engine by running at 
least one hot-start transient cycle. We will precondition your engine by 
running two hot-start transient cycles. Immediately after completing 
each preconditioning cycle, shut down the engine, then start the next 
cycle (including the emission test) as soon as practical. For any repeat 
cycles, start the next cycle within 60 seconds after completing the last 
preconditioning cycle (this is optional for manufacturer testing).
    (3) Hot-running transient cycle. Precondition the engine by running 
at least one hot-running transient cycle. We will precondition your 
engine by running two hot-running transient cycles. Do not shut down the 
engine between cycles. Immediately after completing each preconditioning 
cycle, start the next cycle (including the emission test) as soon as 
practical. For any repeat cycles, start the next cycle within 60 seconds 
after completing the last preconditioning cycle (this is optional for 
manufacturer testing). See Sec. 1065.530(a)(1)(iii) for additional 
instructions if the cycle begins and ends under different operating 
conditions.
    (4) Discrete-mode cycle for steady-state testing. Precondition the 
engine at the

[[Page 153]]

same operating condition as the next test mode, unless the standard-
setting part specifies otherwise. We will precondition your engine by 
running it for at least five minutes before sampling.
    (5) Ramped-modal cycle for steady-state testing. Precondition the 
engine by running at least the second half of the ramped-modal cycle, 
based on the number of test modes. For example, for the five-mode cycle 
specified in 40 CFR 1039.505(b)(1), the second half of the cycle 
consists of modes three through five. We will precondition your engine 
by running one complete ramped-modal cycle. Do not shut down the engine 
between cycles. Immediately after completing each preconditioning cycle, 
start the next cycle (including the emission test) as soon as practical. 
For any repeat cycles, start the next cycle within 60 seconds after 
completing the last preconditioning cycle. See Sec. 1065.530(a)(1)(iii) 
for additional instructions if the cycle begins and ends under different 
operating conditions.
    (d) You may conduct calibrations or verifications on any idle 
equipment or analyzers during engine preconditioning.

[79 FR 23774, Apr. 28, 2014]



Sec. 1065.520  Pre-test verification procedures and pre-test data
collection.

    (a) For tests in which you measure PM emissions, follow the 
procedures for PM sample preconditioning and tare weighing according to 
Sec. 1065.590.
    (b) Unless the standard-setting part specifies different tolerances, 
verify at some point before the test that ambient conditions are within 
the tolerances specified in this paragraph (b). For purposes of this 
paragraph (b), ``before the test'' means any time from a point just 
prior to engine starting (excluding engine restarts) to the point at 
which emission sampling begins.
    (1) Ambient temperature of (20 to 30)  deg.C. See Sec. 1065.530(j) 
for circumstances under which ambient temperatures must remain within 
this range during the test.
    (2) Atmospheric pressure of (80.000 to 103.325) kPa and within [5 
kPa of the value recorded at the time of the last engine map. You are 
not required to verify atmospheric pressure prior to a hot start test 
interval for testing that also includes a cold start.
    (3) Dilution air conditions as specified in Sec. 1065.140, except 
in cases where you preheat your CVS before a cold start test. We 
recommend verifying dilution air conditions just prior to the start of 
each test interval.
    (c) You may test engines at any intake-air humidity, and we may test 
engines at any intake-air humidity.
    (d) Verify that auxiliary-work inputs and outputs are configured as 
they were during engine mapping, as described in Sec. 1065.510(a).
    (e) You may perform a final calibration of the speed, torque, and 
proportional-flow control systems, which may include performing practice 
duty cycles (or portions of duty cycles). This may be done in 
conjunction with the preconditioning in Sec. 1065.518.
    (f) Verify the amount of nonmethane hydrocarbon contamination in the 
exhaust and background HC sampling systems within 8 hours before the 
start of the first test interval of each duty-cycle sequence for 
laboratory tests. You may verify the contamination of a background HC 
sampling system by reading the last bag fill and purge using zero gas. 
For any NMHC measurement system that involves separately measuring 
CH4 and subtracting it from a THC measurement or for any 
CH4 measurement system that uses an NMC, verify the amount of 
THC contamination using only the THC analyzer response. There is no need 
to operate any separate CH4 analyzer for this verification; 
however, you may measure and correct for THC contamination in the 
CH4 sample path for the cases where NMHC is determined by 
subtracting CH4 from THC or, where CH4 is 
determined, using an NMC as configured in Sec. 1065.365(d), (e), and 
(f); and using the calculations in Sec. 1065.660(b)(2). Perform this 
verification as follows:
    (1) Select the HC analyzer range for measuring the flow-weighted 
mean concentration expected at the HC standard.
    (2) Zero the HC analyzer at the analyzer zero or sample port. Note 
that FID zero and span balance gases may be any combination of purified 
air or

[[Page 154]]

purified nitrogen that meets the specifications of Sec. 1065.750. We 
recommend FID analyzer zero and span gases that contain approximately 
the flow-weighted mean concentration of O2 expected during 
testing.
    (3) Span the HC analyzer using span gas introduced at the analyzer 
span or sample port. Span on a carbon number basis of one 
(C1). For example, if you use a C3H8 
span gas of concentration 200 [micro] mol/mol, span the FID to respond 
with a value of 600 [micro] mol/mol.
    (4) Overflow zero gas at the HC probe inlet or into a tee near the 
probe outlet.
    (5) Measure the THC concentration in the sampling and background 
systems as follows:
    (i) For continuous sampling, record the mean THC concentration as 
overflow zero gas flows.
    (ii) For batch sampling, fill the sample medium (e.g., bag) and 
record its mean THC concentration.
    (iii) For the background system, record the mean THC concentration 
of the last fill and purge.
    (6) Record this value as the initial THC concentration, 
xTHC[THC-FID]init, and use it to correct measured values as 
described in Sec. 1065.660.
    (7) You may correct the measured initial THC concentration for drift 
as follows:
    (i) For batch and continuous HC analyzers, after determining the 
initial THC concentration, flow zero gas to the analyzer zero or sample 
port. When the analyzer reading is stable, record the mean analyzer 
value.
    (ii) Flow span gas to the analyzer span or sample port. When the 
analyzer reading is stable, record the mean analyzer value.
    (iii) Use mean analyzer values from paragraphs (f)(2), (f)(3), 
(f)(7)(i), and (f)(7)(ii) of this section to correct the initial THC 
concentration recorded in paragraph (f)(6) of this section for drift, as 
described in Sec. 1065.550.
    (8) If any of the xTHC[THC-FID]init values exceed the 
greatest of the following values, determine the source of the 
contamination and take corrective action, such as purging the system 
during an additional preconditioning cycle or replacing contaminated 
portions:
    (i) 2% of the flow-weighted mean concentration expected at the HC 
(THC or NMHC) standard.
    (ii) 2% of the flow-weighted mean concentration of HC (THC or NMHC) 
measured during testing.
    (iii) 2 [micro] mol/mol.
    (9) If corrective action does not resolve the deficiency, you may 
request to use the contaminated system as an alternate procedure under 
Sec. 1065.10.

[79 FR 23775, Apr. 28, 2014]



Sec. 1065.525  Engine starting, restarting, and shutdown.

    (a) For test intervals that require emission sampling during engine 
starting, start the engine using one of the following methods:
    (1) Start the engine as recommended in the owners manual using a 
production starter motor or air-start system and either an adequately 
charged battery, a suitable power supply, or a suitable compressed air 
source.
    (2) Use the dynamometer to start the engine. To do this, motor the 
engine within [25% of its typical in-use cranking speed. Stop cranking 
within 1 second of starting the engine.
    (3) In the case of hybrid engines, activate the system such that the 
engine will start when its control algorithms determine that the engine 
should provide power instead of or in addition to power from the RESS. 
Unless we specify otherwise, engine starting throughout this part 
generally refers to this step of activating the system on hybrid 
engines, whether or not that causes the engine to start running.
    (b) If the engine does not start after 15 seconds of cranking, stop 
cranking and determine why the engine failed to start, unless the owners 
manual or the service-repair manual describes the longer cranking time 
as normal.
    (c) Respond to engine stalling with the following steps:
    (1) If the engine stalls during warm-up before emission sampling 
begins, restart the engine and continue warm-up.
    (2) If the engine stalls during preconditioning before emission 
sampling begins, restart the engine and restart the preconditioning 
sequence.
    (3) Void the entire test if the engine stalls at any time after 
emission sampling begins, except as described in

[[Page 155]]

Sec. 1065.526. If you do not void the entire test, you must void the 
individual test mode or test interval in which the engine stalls.
    (d) Shut down the engine according to the manufacturer's 
specifications.

[73 FR 37320, June 30, 2008, as amended at 75 FR 68463, Nov. 8, 2010; 76 
FR 57451, Sept. 15, 2011]



Sec. 1065.526  Repeating of void modes or test intervals.

    (a) Test modes and test intervals can be voided because of 
instrument malfunction, engine stalling, emissions exceeding instrument 
ranges, and other unexpected deviations from the specified procedures. 
This section specifies circumstances for which a test mode or test 
interval can be repeated without repeating the entire test.
    (b) This section is intended to result in replicate test modes and 
test intervals that are identical to what would have occurred if the 
cause of the voiding had not occurred. It does not allow you to repeat 
test modes or test intervals in any circumstances that would be 
inconsistent with good engineering judgment. For example, the procedures 
specified here for repeating a mode or interval may not apply for 
certain engines that include hybrid energy storage features or emission 
controls that involve physical or chemical storage of pollutants. This 
section applies for circumstances in which emission concentrations 
exceed the analyzer range only if it is due to operator error or 
analyzer malfunction. It does not apply for circumstances in which the 
emission concentrations exceed the range because they were higher than 
expected.
    (c) If one of the modes of a discrete-mode duty cycle is voided 
while running the duty cycle as provided in this section, you may void 
the results for that individual mode and continue the duty cycle as 
follows:
    (1) If the engine has stalled or been shut down, restart the engine.
    (2) Use good engineering judgment to restart the duty cycle using 
the appropriate steps in Sec. 1065.530(b).
    (3) Stabilize the engine by operating it at the mode at which the 
duty cycle was interrupted and continue with the duty cycle as specified 
in the standard-setting part.
    (d) If an individual mode of a discrete-mode duty cycle sequence is 
voided after running the full duty cycle, you may void results for that 
mode and repeat testing for that mode as follows:
    (1) Use good engineering judgment to restart the test sequence using 
the appropriate steps in Sec. 1065.530(b).
    (2) Stabilize the engine by operating it at that mode.
    (3) Sample emissions over an appropriate test interval.
    (4) If you sampled gaseous and PM emissions over separate test 
intervals for a voided mode, you must void both test intervals and 
repeat sampling of both gaseous and PM emissions for that mode.
    (e) If a transient or ramped-modal cycle test interval is voided as 
provided in this section, you may repeat the test interval as follows:
    (1) Use good engineering judgment to restart (as applicable) and 
precondition the engine to the same condition as would apply for normal 
testing. This may require you to complete the voided test interval. For 
example, you may generally repeat a hot-start test of a heavy-duty 
highway engine after completing the voided hot-start test and allowing 
the engine to soak for 20 minutes.
    (2) Complete the remainder of the test according to the provisions 
in this subpart.
    (f) Keep records from the voided test mode or test interval in the 
same manner as required for unvoided tests.

[79 FR 23776, Apr. 28, 2014]



Sec. 1065.530  Emission test sequence.

    (a) Time the start of testing as follows:
    (1) Perform one of the following if you precondition the engine as 
described in Sec. 1065.518:
    (i) For cold-start duty cycles, shut down the engine. Unless the 
standard-setting part specifies that you may only perform a natural 
engine cooldown, you may perform a forced engine cooldown. Use good 
engineering judgment to set up systems to send cooling air across the 
engine, to send cool oil through the engine lubrication system, to 
remove heat from coolant

[[Page 156]]

through the engine cooling system, and to remove heat from any exhaust 
aftertreatment systems. In the case of a forced aftertreatment cooldown, 
good engineering judgment would indicate that you not start flowing 
cooling air until the aftertreatment system has cooled below its 
catalytic activation temperature. For platinum-group metal catalysts, 
this temperature is about 200  deg.C. Once the aftertreatment system has 
naturally cooled below its catalytic activation temperature, good 
engineering judgment would indicate that you use clean air with a 
temperature of at least 15  deg.C, and direct the air through the 
aftertreatment system in the normal direction of exhaust flow. Do not 
use any cooling procedure that results in unrepresentative emissions 
(see Sec. 1065.10(c)(1)). You may start a cold-start duty cycle when 
the temperatures of an engine's lubricant, coolant, and aftertreatment 
systems are all between (20 and 30)  deg.C.
    (ii) For hot-start emission measurements, shut down the engine 
immediately after completing the last preconditioning cycle. For any 
repeat cycles, start the hot-start transient emission test within 60 
seconds after completing the last preconditioning cycle (this is 
optional for manufacturer testing).
    (iii) For testing that involves hot-stabilized emission 
measurements, such as any steady-state testing with a ramped-modal 
cycle, start the hot-stabilized emission test within 60 seconds after 
completing the last preconditioning cycle (the time between cycles is 
optional for manufacturer testing). If the hot-stabilized cycle begins 
and ends with different operating conditions, add a linear transition 
period of 20 seconds between hot-stabilized cycles where you linearly 
ramp the (denormalized) reference speed and torque values over the 
transition period. See Sec. 1065.501(c)(2)(i) for discrete-mode cycles.
    (2) If you do not precondition the engine as described in Sec. 
1065.518, perform one of the following:
    (i) For cold-start duty cycles, prepare the engine according to 
paragraph (a)(1)(i) of this section.
    (ii) For hot-start duty cycles, first operate the engine at any 
speed above peak-torque speed and at (65 to 85) % of maximum mapped 
power until either the engine coolant, block, or head absolute 
temperature is within [2% of its mean value for at least 2 min or until 
the engine thermostat controls engine temperature. Shut down the engine. 
Start the duty cycle within 20 min of engine shutdown.
    (iii) For testing that involves hot-stabilized emission 
measurements, bring the engine either to warm idle or the first 
operating point of the duty cycle. Start the test within 10 min of 
achieving temperature stability. Determine temperature stability either 
as the point at which the engine coolant, block, or head absolute 
temperature is within [2% of its mean value for at least 2 min, or as 
the point at which the engine thermostat controls engine temperature.
    (b) Take the following steps before emission sampling begins:
    (1) For batch sampling, connect clean storage media, such as 
evacuated bags or tare-weighed filters.
    (2) Start all measurement instruments according to the instrument 
manufacturer's instructions and using good engineering judgment.
    (3) Start dilution systems, sample pumps, cooling fans, and the 
data-collection system.
    (4) Pre-heat or pre-cool heat exchangers in the sampling system to 
within their operating temperature tolerances for a test.
    (5) Allow heated or cooled components such as sample lines, filters, 
chillers, and pumps to stabilize at their operating temperatures.
    (6) Verify that there are no significant vacuum-side leaks according 
to Sec. 1065.345.
    (7) Adjust the sample flow rates to desired levels, using bypass 
flow, if desired.
    (8) Zero or re-zero any electronic integrating devices, before the 
start of any test interval.
    (9) Select gas analyzer ranges. You may automatically or manually 
switch gas analyzer ranges during a test only if switching is performed 
by changing the span over which the digital resolution of the instrument 
is applied. During a test you may not switch the gains

[[Page 157]]

of an analyzer's analog operational amplifier(s).
    (10) Zero and span all continuous analyzers using NIST-traceable 
gases that meet the specifications of Sec. 1065.750. Span FID analyzers 
on a carbon number basis of one (1), C1. For example, if you 
use a C3H8 span gas of concentration 200 [micro] 
mol/mol, span the FID to respond with a value of 600 [micro] mol/mol. 
Span FID analyzers consistent with the determination of their respective 
response factors, RF, and penetration fractions, PF, according to Sec. 
1065.365.
    (11) We recommend that you verify gas analyzer responses after 
zeroing and spanning by sampling a calibration gas that has a 
concentration near one-half of the span gas concentration. Based on the 
results and good engineering judgment, you may decide whether or not to 
re-zero, re-span, or re-calibrate a gas analyzer before starting a test.
    (12) Drain any accumulated condensate from the intake air system 
before starting a duty cycle, as described in Sec. 1065.125(e)(1). If 
engine and aftertreatment preconditioning cycles are run before the duty 
cycle, treat the preconditioning cycles and any associated soak period 
as part of the duty cycle for the purpose of opening drains and draining 
condensate. Note that you must close any intake air condensate drains 
that are not representative of those normally open during in-use 
operation.
    (c) Start and run each test interval as described in this paragraph 
(c). The procedure varies depending on whether the test interval is part 
of a discrete-mode cycle, and whether the test interval includes engine 
starting. Note that the standard-setting part may apply different 
requirements for running test intervals. For example, 40 CFR part 1033 
specifies a different way to perform discrete-mode testing.
    (1) For steady-state discrete-mode duty cycles, start the duty cycle 
with the engine warmed-up and running as described in Sec. 
1065.501(c)(2)(i). Run each mode in the sequence specified in the 
standard-setting part. This will require controlling engine speed, 
engine load, or other operator demand settings as specified in the 
standard-setting part. Simultaneously start any electronic integrating 
devices, continuous data recording, and batch sampling. We recommend 
that you stabilize the engine for at least 5 minutes for each mode. Once 
sampling begins, sample continuously for at least 1 minute. Note that 
longer sample times may be needed for accurately measuring very low 
emission levels.
    (2) For transient and steady-state ramped-modal duty cycles that do 
not include engine starting, start the test interval with the engine 
running as soon as practical after completing engine preconditioning. 
Simultaneously start any electronic integrating devices, continuous data 
recording, batch sampling, and execution of the duty cycle.
    (3) If engine starting is part of the test interval, simultaneously 
start any electronic integrating devices, continuous data recording, and 
batch sampling before attempting to start the engine. Initiate the 
sequence of points in the duty cycle when the engine starts.
    (4) For batch sampling systems, you may advance or delay the start 
and end of sampling at the beginning and end of the test interval to 
improve the accuracy of the batch sample, consistent with good 
engineering judgment.
    (d) At the end of each test interval, continue to operate all 
sampling and dilution systems to allow the sampling system's response 
time to elapse. Then stop all sampling and recording, including the 
recording of background samples. Finally, stop any integrating devices 
and indicate the end of the duty cycle in the recorded data.
    (e) Shut down the engine if you have completed testing or if it is 
part of the duty cycle.
    (f) If testing involves another duty cycle after a soak period with 
the engine off, start a timer when the engine shuts down, and repeat the 
steps in paragraphs (b) through (e) of this section as needed.
    (g) Take the following steps after emission sampling is complete:
    (1) For any proportional batch sample, such as a bag sample or PM 
sample, verify that proportional sampling was maintained according to 
Sec. 1065.545.

[[Page 158]]

Void any samples that did not maintain proportional sampling according 
to Sec. 1065.545.
    (2) Place any used PM samples into covered or sealed containers and 
return them to the PM-stabilization environment. Follow the PM sample 
post-conditioning and total weighing procedures in Sec. 1065.595.
    (3) As soon as practical after the duty cycle is complete, or during 
the soak period if practical, perform the following:
    (i) Zero and span all batch gas analyzers no later than 30 minutes 
after the duty cycle is complete, or during the soak period if 
practical.
    (ii) Analyze any conventional gaseous batch samples no later than 30 
minutes after the duty cycle is complete, or during the soak period if 
practical.
    (iii) Analyze background samples no later than 60 minutes after the 
duty cycle is complete.
    (iv) Analyze non-conventional gaseous batch samples, such as ethanol 
(NMHCE) as soon as practical using good engineering judgment.
    (4) After quantifying exhaust gases, verify drift as follows:
    (i) For batch and continuous gas analyzers, record the mean analyzer 
value after stabilizing a zero gas to the analyzer. Stabilization may 
include time to purge the analyzer of any sample gas, plus any 
additional time to account for analyzer response.
    (ii) Record the mean analyzer value after stabilizing the span gas 
to the analyzer. Stabilization may include time to purge the analyzer of 
any sample gas, plus any additional time to account for analyzer 
response.
    (iii) Use these data to validate and correct for drift as described 
in Sec. 1065.550.
    (h) Unless the standard-setting part specifies otherwise, determine 
whether or not the test meets the cycle-validation criteria in Sec. 
1065.514.
    (1) If the criteria void the test, you may retest using the same 
denormalized duty cycle, or you may re-map the engine, denormalize the 
reference duty cycle based on the new map and retest the engine using 
the new denormalized duty cycle.
    (2) If the criteria void the test for a constant-speed engine only 
during commands of maximum test torque, you may do the following:
    (i) Determine the first and last feedback speeds at which maximum 
test torque was commanded.
    (ii) If the last speed is greater than or equal to 90% of the first 
speed, the test is void. You may retest using the same denormalized duty 
cycle, or you may re-map the engine, denormalize the reference duty 
cycle based on the new map and retest the engine using the new 
denormalized duty cycle.
    (iii) If the last speed is less than 90% of the first speed, reduce 
maximum test torque by 5%, and proceed as follows:
    (A) Denormalize the entire duty cycle based on the reduced maximum 
test torque according to Sec. 1065.512.
    (B) Retest the engine using the denormalized test cycle that is 
based on the reduced maximum test torque.
    (C) If your engine still fails the cycle criteria, reduce the 
maximum test torque by another 5% of the original maximum test torque.
    (D) If your engine fails after repeating this procedure four times, 
such that your engine still fails after you have reduced the maximum 
test torque by 20% of the original maximum test torque, notify us and we 
will consider specifying a more appropriate duty cycle for your engine 
under the provisions of Sec. 1065.10(c).
    (i) [Reserved]
    (j) Measure and record ambient temperature, pressure, and humidity, 
as appropriate. For testing the following engines, you must record 
ambient temperature continuously to verify that it remains within the 
pre-test temperature range as specified in Sec. 1065.520(b):
    (1) Air-cooled engines.
    (2) Engines equipped with auxiliary emission control devices that 
sense and respond to ambient temperature.
    (3) Any other engine for which good engineering judgment indicates 
this is necessary to remain consistent with Sec. 1065.10(c)(1).

[73 FR 37321, June 30, 2008, as amended at 75 FR 23043, Apr. 30, 2010; 
76 FR 57451, Sept. 15, 2011; 79 FR 23776, Apr. 28, 2014]

[[Page 159]]



Sec. 1065.545  Verification of proportional flow control for batch
sampling.

    For any proportional batch sample such as a bag or PM filter, 
demonstrate that proportional sampling was maintained using one of the 
following, noting that you may omit up to 5% of the total number of data 
points as outliers:
    (a) For any pair of flow rates, use recorded sample and total flow 
rates, where total flow rate means the raw exhaust flow rate for raw 
exhaust sampling and the dilute exhaust flow rate for CVS sampling, or 
their 1 Hz means with the statistical calculations in Sec. 1065.602. 
Determine the standard error of the estimate, SEE, of the sample flow 
rate versus the total flow rate. For each test interval, demonstrate 
that SEE was less than or equal to 3.5% of the mean sample flow rate.
    (b) For any pair of flow rates, use recorded sample and total flow 
rates, where total flow rate means the raw exhaust flow rate for raw 
exhaust sampling and the dilute exhaust flow rate for CVS sampling, or 
their 1 Hz means to demonstrate that each flow rate was constant within 
[2.5% of its respective mean or target flow rate. You may use the 
following options instead of recording the respective flow rate of each 
type of meter:
    (1) Critical-flow venturi option. For critical-flow venturis, you 
may use recorded venturi-inlet conditions or their 1 Hz means. 
Demonstrate that the flow density at the venturi inlet was constant 
within [2.5% of the mean or target density over each test interval. For 
a CVS critical-flow venturi, you may demonstrate this by showing that 
the absolute temperature at the venturi inlet was constant within [4% of 
the mean or target absolute temperature over each test interval.
    (2) Positive-displacement pump option. You may use recorded pump-
inlet conditions or their 1 Hz means. Demonstrate that the flow density 
at the pump inlet was constant within [2.5% of the mean or target 
density over each test interval. For a CVS pump, you may demonstrate 
this by showing that the absolute temperature at the pump inlet was 
constant within [2% of the mean or target absolute temperature over each 
test interval.
    (c) Using good engineering judgment, demonstrate with an engineering 
analysis that the proportional-flow control system inherently ensures 
proportional sampling under all circumstances expected during testing. 
For example, you might use CFVs for both sample flow and total dilute 
exhaust (CVS) flow and demonstrate that they always have the same inlet 
pressures and temperatures and that they always operate under critical-
flow conditions.

[79 FR 23777, Apr. 28, 2014]



Sec. 1065.546  Verification of minimum dilution ratio for PM batch 
sampling.

    Use continuous flows and/or tracer gas concentrations for transient 
and ramped-modal cycles to verify the minimum dilution ratios for PM 
batch sampling as specified in Sec. 1065.140(e)(2) over the test 
interval. You may use mode-average values instead of continuous 
measurements for discrete mode steady-state duty cycles. Determine the 
minimum primary and minimum overall dilution ratios using one of the 
following methods (you may use a different method for each stage of 
dilution):
    (a) Determine minimum dilution ratio based on molar flow data. This 
involves determination of at least two of the following three 
quantities: raw exhaust flow (or previously diluted flow), dilution air 
flow, and dilute exhaust flow. You may determine the raw exhaust flow 
rate based on the measured intake air or fuel flow rate and the raw 
exhaust chemical balance terms as given in Sec. 1065.655(f). You may 
determine the raw exhaust flow rate based on the measured intake air and 
dilute exhaust molar flow rates and the dilute exhaust chemical balance 
terms as given in Sec. 1065.655(g). You may alternatively estimate the 
molar raw exhaust flow rate based on intake air, fuel rate measurements, 
and fuel properties, consistent with good engineering judgment.
    (b) Determine minimum dilution ratio based on tracer gas (e.g., 
CO2) concentrations in the raw (or previously diluted) and 
dilute exhaust corrected for any removed water.

[[Page 160]]

    (c) Use good engineering judgment to develop your own method of 
determining dilution ratios.

[75 FR 23043, Apr. 30, 2010, as amended at 76 FR 57451, Sept. 15, 2011; 
79 FR 23778, Apr. 28, 2014; 81 FR 74169, Oct. 25, 2016]



Sec. 1065.550  Gas analyzer range verification and drift verification.

    (a) Range verification. If an analyzer operated above 100% of its 
range at any time during the test, perform the following steps:
    (1) For batch sampling, re-analyze the sample using the lowest 
analyzer range that results in a maximum instrument response below 100%. 
Report the result from the lowest range from which the analyzer operates 
below 100% of its range.
    (2) For continuous sampling, repeat the entire test using the next 
higher analyzer range. If the analyzer again operates above 100% of its 
range, repeat the test using the next higher range. Continue to repeat 
the test until the analyzer always operates at less than 100% of its 
range.
    (b) Drift verification. Gas analyzer drift verification is required 
for all gaseous exhaust constituents for which an emission standard 
applies. It is also required for CO2 even if there is no 
CO2 emission standard. It is not required for other gaseous 
exhaust constituents for which only a reporting requirement applies 
(such as CH4 and N2O).
    (1) Verify drift using one of the following methods:
    (i) For regulated exhaust constituents determined from the mass of a 
single component, perform drift verification based on the regulated 
constituent. For example, when NOX mass is determined with a 
dry sample measured with a CLD and the removed water is corrected based 
on measured CO2, CO, THC, and NOX concentrations, 
you must verify the calculated NOX value.
    (ii) For regulated exhaust constituents determined from the masses 
of multiple subcomponents, perform the drift verification based on 
either the regulated constituent or all the mass subcomponents. For 
example, when NOX is measured with separate NO and 
NO2 analyzers, you must verify either the NOX 
value or both the NO and NO2 values.
    (iii) For regulated exhaust constituents determined from the 
concentrations of multiple gaseous emission subcomponents prior to 
performing mass calculations, perform drift verification on the 
regulated constituent. You may not verify the concentration 
subcomponents (e.g., THC and CH4 for NMHC) separately. For 
example, for NMHC measurements, perform drift verification on NMHC; do 
not verify THC and CH4 separately.
    (2) Drift verification requires two sets of emission calculations. 
For each set of calculations, include all the constituents in the drift 
verification. Calculate one set using the data before drift correction 
and calculate the other set after correcting all the data for drift 
according to Sec. 1065.672. Note that for purposes of drift 
verification, you must leave unaltered any negative emission results 
over a given test interval (i.e., do not set them to zero). These 
unaltered results are used when verifying either test interval results 
or composite brake-specific emissions over the entire duty cycle for 
drift. For each constituent to be verified, both sets of calculations 
must include the following:
    (i) Calculated mass (or mass rate) emission values over each test 
interval.
    (ii) If you are verifying each test interval based on brake-specific 
values, calculate brake-specific emission values over each test 
interval.
    (iii) If you are verifying over the entire duty cycle, calculate 
composite brake-specific emission values.
    (3) The duty cycle is verified for drift if you satisfy the 
following criteria:
    (i) For each regulated gaseous exhaust constituent, you must satisfy 
one of the following:
    (A) For each test interval of the duty cycle, the difference between 
the uncorrected and the corrected brake-specific emission values of the 
regulated constituent must be within [4% of the uncorrected value or the 
applicable emissions standard, whichever is greater. Alternatively, the 
difference between the uncorrected and the corrected emission mass (or 
mass rate) values of the regulated constituent must be within [4% of the 
uncorrected

[[Page 161]]

value or the composite work (or power) multiplied by the applicable 
emissions standard, whichever is greater. For purposes of verifying each 
test interval, you may use either the reference or actual composite work 
(or power).
    (B) For each test interval of the duty cycle and for each mass 
subcomponent of the regulated constituent, the difference between the 
uncorrected and the corrected brake-specific emission values must be 
within [4% of the uncorrected value. Alternatively, the difference 
between the uncorrected and the corrected emissions mass (or mass rate) 
values must be within [4% of the uncorrected value.
    (C) For the entire duty cycle, the difference between the 
uncorrected and the corrected composite brake-specific emission values 
of the regulated constituent must be within [4% of the uncorrected value 
or applicable emission standard, whichever is greater.
    (D) For the entire duty cycle and for each subcomponent of the 
regulated constituent, the difference between the uncorrected and the 
corrected composite brake-specific emission values must be within [4% of 
the uncorrected value.
    (ii) Where no emission standard applies for CO2, you must 
satisfy one of the following:
    (A) For each test interval of the duty cycle, the difference between 
the uncorrected and the corrected brake-specific CO2 values 
must be within [4% of the uncorrected value; or the difference between 
the uncorrected and the corrected CO2 mass (or mass rate) 
values must be within [4% of the uncorrected value.
    (B) For the entire duty cycle, the difference between the 
uncorrected and the corrected composite brake-specific CO2 
values must be within [4% of the uncorrected value.
    (4) If the test is not verified for drift as described in paragraph 
(b)(1) of this section, you may consider the test results for the duty 
cycle to be valid only if, using good engineering judgment, the observed 
drift does not affect your ability to demonstrate compliance with the 
applicable emission standards. For example, if the drift-corrected value 
is less than the standard by at least two times the absolute difference 
between the uncorrected and corrected values, you may consider the data 
to be verified for demonstrating compliance with the applicable 
standard.

[79 FR 23778, Apr. 28, 2014]



Sec. 1065.590  PM sampling media (e.g., filters) preconditioning 
and tare weighing.

    Before an emission test, take the following steps to prepare PM 
sampling media (e.g., filters) and equipment for PM measurements:
    (a) Make sure the balance and PM-stabilization environments meet the 
periodic verifications in Sec. 1065.390.
    (b) Visually inspect unused sample media (e.g., filters) for defects 
and discard defective media.
    (c) To handle PM sampling media (e.g., filters), use electrically 
grounded tweezers or a grounding strap, as described in Sec. 1065.190.
    (d) Place unused sample media (e.g., filters) in one or more 
containers that are open to the PM-stabilization environment. If you are 
using filters, you may place them in the bottom half of a filter 
cassette.
    (e) Stabilize sample media (e.g., filters) in the PM-stabilization 
environment. Consider an unused sample medium stabilized as long as it 
has been in the PM-stabilization environment for a minimum of 30 min, 
during which the PM-stabilization environment has been within the 
specifications of Sec. 1065.190.
    (f) Weigh the sample media (e.g., filters) automatically or 
manually, as follows:
    (1) For automatic weighing, follow the automation system 
manufacturer's instructions to prepare samples for weighing. This may 
include placing the samples in a special container.
    (2) Use good engineering judgment to determine if substitution 
weighing is necessary to show that an engine meets the applicable 
standard. You may follow the substitution weighing procedure in 
paragraph (j) of this section, or you may develop your own procedure.
    (g) Correct the measured mass of each sample medium (e.g., filter) 
for buoyancy as described in Sec. 1065.690. These buoyancy-corrected 
values are subsequently subtracted from the post-

[[Page 162]]

test mass of the corresponding sample media (e.g., filters) and 
collected PM to determine the mass of PM emitted during the test.
    (h) You may repeat measurements to determine the mean mass of each 
sample medium (e.g., filter). Use good engineering judgment to exclude 
outliers from the calculation of mean mass values.
    (i) If you use filters as sample media, load unused filters that 
have been tare-weighed into clean filter cassettes and place the loaded 
cassettes in a clean, covered or sealed container before removing them 
from the stabilization environment for transport to the test site for 
sampling. We recommend that you keep filter cassettes clean by 
periodically washing or wiping them with a compatible solvent applied 
using a lint-free cloth. Depending upon your cassette material, ethanol 
(C2H5OH) might be an acceptable solvent. Your 
cleaning frequency will depend on your engine's level of PM and HC 
emissions.
    (j) Substitution weighing involves measurement of a reference weight 
before and after each weighing of the PM sampling medium (e.g., the 
filter). While substitution weighing requires more measurements, it 
corrects for a balance's zero-drift and it relies on balance linearity 
only over a small range. This is most advantageous when quantifying net 
PM masses that are less than 0.1% of the sample medium's mass. However, 
it may not be advantageous when net PM masses exceed 1% of the sample 
medium's mass. If you utilize substitution weighing, it must be used for 
both pre-test and post-test weighing. The same substitution weight must 
be used for both pre-test and post-test weighing. Correct the mass of 
the substitution weight for buoyancy if the density of the substitution 
weight is less than 2.0 g/cm\3\. The following steps are an example of 
substitution weighing:
    (1) Use electrically grounded tweezers or a grounding strap, as 
described in Sec. 1065.190.
    (2) Use a static neutralizer as described in Sec. 1065.190 to 
minimize static electric charge on any object before it is placed on the 
balance pan.
    (3) Select and weigh a substitution weight that meets the 
requirements for calibration weights found in Sec. 1065.790. The 
substitution weight must also have the same density as the weight you 
use to span the microbalance, and be similar in mass to an unused sample 
medium (e.g., filter). A 47 mm PTFE membrane filter will typically have 
a mass in the range of 80 to 100 mg.
    (4) Record the stable balance reading, then remove the substitution 
weight.
    (5) Weigh an unused sample medium (e.g., a new filter), record the 
stable balance reading and record the balance environment's dewpoint, 
ambient temperature, and atmospheric pressure.
    (6) Reweigh the substitution weight and record the stable balance 
reading.
    (7) Calculate the arithmetic mean of the two substitution-weight 
readings that you recorded immediately before and after weighing the 
unused sample. Subtract that mean value from the unused sample reading, 
then add the true mass of the substitution weight as stated on the 
substitution-weight certificate. Record this result. This is the unused 
sample's tare weight without correcting for buoyancy.
    (8) Repeat these substitution-weighing steps for the remainder of 
your unused sample media.
    (9) Once weighing is completed, follow the instructions given in 
paragraphs (g) through (i) of this section.

[73 FR 37323, June 30, 2008, as amended at 81 FR 74169, Oct. 25, 2016]



Sec. 1065.595  PM sample post-conditioning and total weighing.

    After testing is complete, return the sample media (e.g., filters) 
to the weighing and PM-stabilization environments.
    (a) Make sure the weighing and PM-stabilization environments meet 
the ambient condition specifications in Sec. 1065.190(e)(1). If those 
specifications are not met, leave the test sample media (e.g., filters) 
covered until proper conditions have been met.
    (b) In the PM-stabilization environment, remove PM samples from 
sealed containers. If you use filters, you may remove them from their 
cassettes before or after stabilization. We recommend always removing 
the top portion of the cassette before stabilization. When you remove a 
filter from a cassette, separate the top half of the

[[Page 163]]

cassette from the bottom half using a cassette separator designed for 
this purpose.
    (c) To handle PM samples, use electrically grounded tweezers or a 
grounding strap, as described in Sec. 1065.190.
    (d) Visually inspect the sampling media (e.g., filters) and 
collected particulate. If either the sample media (e.g., filters) or 
particulate sample appear to have been compromised, or the particulate 
matter contacts any surface other than the filter, the sample may not be 
used to determine particulate emissions. In the case of contact with 
another surface, clean the affected surface before continuing.
    (e) To stabilize PM samples, place them in one or more containers 
that are open to the PM-stabilization environment, as described in Sec. 
1065.190. If you expect that a sample medium's (e.g., filter's) total 
surface concentration of PM will be less than 400 [micro] g, assuming a 
38 mm diameter filter stain area, expose the filter to a PM-
stabilization environment meeting the specifications of Sec. 1065.190 
for at least 30 minutes before weighing. If you expect a higher PM 
concentration or do not know what PM concentration to expect, expose the 
filter to the stabilization environment for at least 60 minutes before 
weighing. Note that 400 [micro] g on sample media (e.g., filters) is an 
approximate net mass of 0.07 g/kW [middot] hr for a hot-start test with 
compression-ignition engines tested according to 40 CFR part 86, subpart 
N, or 50 mg/mile for light-duty vehicles tested according to 40 CFR part 
86, subpart B.
    (f) Repeat the procedures in Sec. 1065.590(f) through (i) to 
determine post-test mass of the sample media (e.g., filters).
    (g) Subtract each buoyancy-corrected tare mass of the sample medium 
(e.g., filter) from its respective buoyancy-corrected mass. The result 
is the net PM mass, mPM. Use mPM in emission 
calculations in Sec. 1065.650.

[73 FR 37323, June 30, 2008]



              Subpart G_Calculations and Data Requirements



Sec. 1065.601  Overview.

    (a) This subpart describes how to--
    (1) Use the signals recorded before, during, and after an emission 
test to calculate brake-specific emissions of each measured exhaust 
constituent.
    (2) Perform calculations for calibrations and performance checks.
    (3) Determine statistical values.
    (b) You may use data from multiple systems to calculate test results 
for a single emission test, consistent with good engineering judgment. 
You may also make multiple measurements from a single batch sample, such 
as multiple weighings of a PM filter or multiple readings from a bag 
sample. Although you may use an average of multiple measurements from a 
single test, you may not use test results from multiple emission tests 
to report emissions.
    (1) We allow weighted means where appropriate.
    (2) You may discard statistical outliers, but you must report all 
results.
    (3) For emission measurements related to durability testing, we may 
allow you to exclude certain test points other than statistical outliers 
relative to compliance with emission standards, consistent with good 
engineering judgment and normal measurement variability; however, you 
must include these results when calculating the deterioration factor. 
This would allow you to use durability data from an engine that has an 
intermediate test result above the standard that cannot be discarded as 
a statistical outlier, as long as good engineering judgment indicates 
that the test result does not represent the engine's actual emission 
level. Note that good engineering judgment would preclude you from 
excluding endpoints. Also, if normal measurement variability causes 
emission results below zero, include the negative result in calculating 
the deterioration factor to avoid an upward bias. These provisions 
related to durability testing are intended to address very stringent 
standards where measurement variability is large relative to the 
emission standard.
    (c) You may use any of the following calculations instead of the 
calculations specified in this subpart G:

[[Page 164]]

    (1) Mass-based emission calculations prescribed by the International 
Organization for Standardization (ISO), according to ISO 8178, except 
the following:
    (i) ISO 8178-1 Section 14.4, NOX Correction for Humidity 
and Temperature. See Sec. 1065.670 for approved methods for humidity 
corrections.
    (ii) ISO 8178-1 Section 15.1, Particulate Correction Factor for 
Humidity.
    (2) Other calculations that you show are equivalent to within [0.1% 
of the brake-specific emission results determined using the calculations 
specified in this subpart G.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37324, June 30, 2008; 
74 FR 56516, Oct. 30, 2009; 75 FR 23044, Apr. 30, 2010; 79 FR 23778, 
Apr. 28, 2014]



Sec. 1065.602  Statistics.

    (a) Overview. This section contains equations and example 
calculations for statistics that are specified in this part. In this 
section we use the letter ``y'' to denote a generic measured quantity, 
the superscript over-bar ``-`` to denote an arithmetic mean, 
and the subscript ``ref'' to denote the reference quantity 
being measured.
    (b) Arithmetic mean. Calculate an arithmetic mean, y, as follows:
    [GRAPHIC] [TIFF OMITTED] TR30AP10.003
    
Example:

N = 3
y1 = 10.60
y2 = 11.91
yN = y3 = 11.09
[GRAPHIC] [TIFF OMITTED] TR30AP10.004

y = 11.20

    (c) Standard deviation. Calculate the standard deviation for a non-
biased (e.g., N-1) sample, s, as follows:
[GRAPHIC] [TIFF OMITTED] TR13JY05.024

Example:

N = 3
y1 = 10.60
y2 = 11.91
yN = y3 = 11.09
y = 11.20
[GRAPHIC] [TIFF OMITTED] TR13JY05.025


[[Page 165]]


sy = 0.6619

    (d) Root mean square. Calculate a root mean square, rmsy, 
as follows:
[GRAPHIC] [TIFF OMITTED] TR13JY05.026

Example:

N = 3
y1 = 10.60
y2 = 11.91
yN = y3 = 11.09
[GRAPHIC] [TIFF OMITTED] TR13JY05.027

rmsy = 11.21

    (e) Accuracy. Determine accuracy as described in this paragraph (e). 
Make multiple measurements of a standard quantity to create a set of 
observed values, yi, and compare each observed value to the 
known value of the standard quantity. The standard quantity may have a 
single known value, such as a gas standard, or a set of known values of 
negligible range, such as a known applied pressure produced by a 
calibration device during repeated applications. The known value of the 
standard quantity is represented by yrefi . If you use a 
standard quantity with a single value, yrefi would be 
constant. Calculate an accuracy value as follows:
[GRAPHIC] [TIFF OMITTED] TR30AP10.005

Example:

yref = 1800.0
N = 3
y1 = 1806.4
y2 = 1803.1
y3 = 1798.9
[GRAPHIC] [TIFF OMITTED] TR30AP10.006

[GRAPHIC] [TIFF OMITTED] TR30AP10.007

accuracy = 2.8

    (f) t-test. Determine if your data passes a t-test by using the 
following equations and tables:
    (1) For an unpaired t-test, calculate the t statistic and its number 
of degrees of freedom, v, as follows:

[[Page 166]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.010

    (2) For a paired t-test, calculate the t statistic and its number of 
degrees of freedom, v, as follows, noting that the [egr]i are 
the errors (e.g., differences) between each pair of yrefi and 
yi:

[[Page 167]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.011


[[Page 168]]


[GRAPHIC] [TIFF OMITTED] TR28AP14.012


 Table 1 of Sec. 1065.602--Critical t Values Versus Number of Degrees
                            of Freedom, v \1\
------------------------------------------------------------------------
                                                       Confidence
                       n                       -------------------------
                                                    90%          95%
------------------------------------------------------------------------
1.............................................        6.314       12.706
2.............................................        2.920        4.303
3.............................................        2.353        3.182
4.............................................        2.132        2.776
5.............................................        2.015        2.571
6.............................................        1.943        2.447
7.............................................        1.895        2.365
8.............................................        1.860        2.306
9.............................................        1.833        2.262
10............................................        1.812        2.228
11............................................        1.796        2.201
12............................................        1.782        2.179
13............................................        1.771        2.160
14............................................        1.761        2.145
15............................................        1.753        2.131
16............................................        1.746        2.120
18............................................        1.734        2.101
20............................................        1.725        2.086
22............................................        1.717        2.074
24............................................        1.711        2.064
26............................................        1.706        2.056
28............................................        1.701        2.048
30............................................        1.697        2.042
35............................................        1.690        2.030
40............................................        1.684        2.021
50............................................        1.676        2.009
70............................................        1.667        1.994
100...........................................        1.660        1.984
1000 +........................................        1.645        1.960
------------------------------------------------------------------------
\1\ Use linear interpolation to establish values not shown here.

    (g) F-test. Calculate the F statistic as follows:
    [GRAPHIC] [TIFF OMITTED] TR13JY05.036
    
Example:

[[Page 169]]

[GRAPHIC] [TIFF OMITTED] TR13JY05.037

[GRAPHIC] [TIFF OMITTED] TR13JY05.038

[GRAPHIC] [TIFF OMITTED] TR13JY05.039

F = 1.268

    (1) For a 90% confidence F-test, use Table 2 of this section to 
compare F to the Fcrit90 values tabulated versus (N-1) and 
(Nref-1). If F is less than Fcrit90, then F passes 
the F-test at 90% confidence.
    (2) For a 95% confidence F-test, use Table 3 of this section to 
compare F to the Fcrit95 values tabulated versus (N-1) and 
(Nref-1). If F is less than Fcrit95, then F passes 
the F-test at 95% confidence.

[[Page 170]]

[GRAPHIC] [TIFF OMITTED] TR13JY05.017


[[Page 171]]


[GRAPHIC] [TIFF OMITTED] TR13JY05.018

    (h) Slope. Calculate a least-squares regression slope, 
a1y, as follows:

[[Page 172]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.021

Example:

N = 6000
y1 = 2045.8
y = 1050.1
yref 1 = 2045.0
yref = 1055.3
[GRAPHIC] [TIFF OMITTED] TR15SE11.022

a1y = 1.0110

    (i) Intercept. Calculate a least-squares regression intercept, 
a0y, as follows:
[GRAPHIC] [TIFF OMITTED] TR13JY05.042

Example:

y = 1050.1
a1y = 1.0110
yref = 1055.3
a0y = 1050.1 - (1.0110 [middot] 1055.3)
a0y = -16.8083

    (j) Standard estimate of error. Calculate a standard estimate of 
error, SEE, as follows:

[GRAPHIC] [TIFF OMITTED] TR25OC16.308

Eq. 1065.602-11
    Example: 
N = 6000
y1 = 2045.8
a0y = -16.8083
a1y = 1.0110
yref1 = 2045.0
[GRAPHIC] [TIFF OMITTED] TR25OC16.313


[[Page 173]]


SEEy = 5.348
    (k) Coefficient of determination. Calculate a coefficient of 
determination, r\2\, as follows:
[GRAPHIC] [TIFF OMITTED] TR13JY05.045

Example:

N = 6000
y1 = 2045.8
a0y = -16.8083
a1y = 1.0110
yrefi = 2045.0
y = 1480.5
[GRAPHIC] [TIFF OMITTED] TR13JY05.046

[GRAPHIC] [TIFF OMITTED] TR13JY05.174

    (l) Flow-weighted mean concentration. In some sections of this part, 
you may need to calculate a flow-weighted mean concentration to 
determine the applicability of certain provisions. A flow-weighted mean 
is the mean of a quantity after it is weighted proportional to a 
corresponding flow rate. For example, if a gas concentration is measured 
continuously from the raw exhaust of an engine, its flow-weighted mean 
concentration is the sum of the products of each recorded concentration 
times its respective exhaust molar flow rate, divided by the sum of the 
recorded flow rate values. As another example, the bag concentration 
from a CVS system is the same as the flow-weighted mean concentration 
because the CVS system itself flow-weights the bag concentration. You 
might already expect a certain flow-weighted mean concentration of an 
emission at its standard based on previous testing with similar engines 
or testing with similar equipment and instruments. If you need to 
estimate your expected flow-weighted mean concentration of an emission 
at its standard, we recommend using the following examples as a guide 
for how to estimate the flow-weighted mean concentration expected at the 
standard. Note that these examples are not exact and that they contain 
assumptions that are not always valid. Use good engineering judgment to 
determine if you can use similar assumptions.
    (1) To estimate the flow-weighted mean raw exhaust NOX 
concentration from a turbocharged heavy-duty compression-ignition engine 
at a NOX standard of 2.5 g/(kW [middot] hr), you may do the 
following:
    (i) Based on your engine design, approximate a map of maximum torque 
versus speed and use it with the applicable normalized duty cycle in the 
standard-setting part to generate a reference duty cycle as described in 
Sec. 1065.610. Calculate the total reference work, Wref, as 
described in Sec. 1065.650. Divide the reference work by the duty 
cycle's time interval, Dtdutycycle, to determine mean 
reference power, Pref.

    (ii) Based on your engine design, estimate maximum power, 
Pmax, the design speed at maximum power, fnmax, 
the design maximum intake manifold boost pressure, pinmax, 
and temperature, Tinmax. Also, estimate a mean fraction of 
power that is lost due to friction and pumping, pfrict. Use 
this information along with the engine displacement

[[Page 174]]

volume, Vdisp, an approximate volumetric efficiency, 
hV, and the number of engine strokes per power stroke (two-
stroke or four-stroke), Nstroke, to estimate the maximum raw 
exhaust molar flow rate, nexhmax.
    (iii) Use your estimated values as described in the following 
example calculation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.023

Example:

eNOx = 2.5 g/(kW [middot] hr)
Wref = 11.883 kW [middot] hr
MNOx = 46.0055 g/mol = 46.0055 [middot] 10-\6\ g/
          [micro] mol
Dtdutycycle = 20 min = 1200 s
Pref = 35.65 kW
Pfrict = 15%
Pmax = 125 kW
pmax = 300 kPa = 300,000 Pa
Vdisp = 3.0 l = 0.0030 m\3\/r
fnmax = 2,800 r/min = 46.67 r/s
Nstroke = 4
h V = 0.9
R = 8.314472 J/(mol [middot] K)
Tmax = 348.15 K
[GRAPHIC] [TIFF OMITTED] TR15SE11.024

nexhmax = 6.53 mol/s
[GRAPHIC] [TIFF OMITTED] TR15SE11.025

xexp = 189.4 [micro] mol/mol

    (2) To estimate the flow-weighted mean NMHC concentration in a CVS 
from a naturally aspirated nonroad spark-ignition engine at an NMHC 
standard of 0.5 g/(kW [middot] hr), you may do the following:

[[Page 175]]

    (i) Based on your engine design, approximate a map of maximum torque 
versus speed and use it with the applicable normalized duty cycle in the 
standard-setting part to generate a reference duty cycle as described in 
Sec. 1065.610. Calculate the total reference work, Wref, as 
described in Sec. 1065.650.
    (ii) Multiply your CVS total molar flow rate by the time interval of 
the duty cycle, Dtdutycycle. The result is the total diluted 
exhaust flow of the ndexh.
    (iii) Use your estimated values as described in the following 
example calculation:
[GRAPHIC] [TIFF OMITTED] TR13JY05.051

Example:

eNMHC = 1.5 g/(kW [middot] hr)
Wref = 5.389 kW [middot] hr
MNMHC = 13.875389 g/mol = 13.875389 [middot] 10-6 
          g/[micro] mol
ndexh = 6.021 mol/s
Dtdutycycle = 30 min = 1800 s
[GRAPHIC] [TIFF OMITTED] TR13JY05.052

xNMHC = 53.8 [micro] mol/mol

[70 FR 40516, July 13, 2005, as amended at 73 FR 37324, June 30, 2008; 
75 FR 23044, Apr. 30, 2010; 76 FR 57452, Sept. 15, 2011; 79 FR 23779, 
Apr. 28, 2014; 81 FR 74170, Oct. 25, 2016]

    Editorial Note: At 79 FR 23779, Apr. 28, 2014, Sec. 1065.605 was 
amended and paragraph (k) could not be revised because the text was not 
provided; however, the amendment could not be incorporated due to 
inaccurate amendatory instruction.



Sec. 1065.610  Duty cycle generation.

    This section describes how to generate duty cycles that are specific 
to your engine, based on the normalized duty cycles in the standard-
setting part. During an emission test, use a duty cycle that is specific 
to your engine to command engine speed, torque, and power, as 
applicable, using an engine dynamometer and an engine operator demand. 
Paragraph (a) of this section describes how to ``normalize'' your 
engine's map to determine the maximum test speed and torque for your 
engine. The rest of this section describes how to use these values to 
``denormalize'' the duty cycles in the standard-setting parts, which are 
all published on a normalized basis. Thus, the term ``normalized'' in 
paragraph (a) of this section refers to different values than it does in 
the rest of the section.
    (a) Maximum test speed, fntest. This section generally 
applies to duty cycles for variable-speed engines. For constant-speed 
engines subject to duty cycles that specify normalized speed commands, 
use the no-load governed speed as the measured fntest. This 
is the highest engine speed where an engine outputs zero torque. For 
variable-speed engines, determine fntest as follows:
    (1) Develop a measured value for fntest as follows:
    (i) Determine maximum power, Pmax, from the engine map 
generated according to Sec. 1065.510 and calculate the value for power 
equal to 98% of Pmax.
    (ii) Determine the lowest and highest engine speeds corresponding to 
98% of Pmax, using linear interpolation, and no 
extrapolation, as appropriate.
    (iii) Determine the engine speed corresponding to maximum power, 
fnPmax, by calculating the average of the two speed values 
from paragraph (a)(1)(ii) of this section. If there is only one speed 
where power is equal to 98% of Pmax, take fnPmax 
as the speed at which Pmax occurs.
    (iv) Transform the map into a normalized power-versus-speed map by 
dividing power terms by Pmax and dividing speed terms by 
fnPmax. Use the following equation to calculate a quantity 
representing the sum of squares from the normalized map:

[[Page 176]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.015

    (v) Determine the maximum value for the sum of the squares from the 
map and multiply that value by 0.98.
    (vi) Determine the lowest and highest engine speeds corresponding to 
the value calculated in paragraph (a)(1)(v) of this section, using 
linear interpolation as appropriate. Calculate fntest as the 
average of these two speed values. If there is only one speed 
corresponding to the value calculated in paragraph (a)(1)(v) of this 
section, take fntest as the speed where the maximum of the 
sum of the squares occurs.
    (vii) The following example illustrates a calculation of 
fntest:

    Pmax = 230.0

(fn1 = 2360, P1 = 222.5, fnnorm1 = 
          1.002, Pnorm1 = 0.9675)
(fn2 = 2364, P2 = 226.8, fnnorm2 = 
          1.004, Pnorm2 = 0.9859)
(fn3 = 2369, P3 = 228.6, fnnorm3 = 
          1.006, Pnorm3 = 0.9940)
(fn4 = 2374, P4 = 218.7, fnnorm4 = 
          1.008, Pnorm4 = 0.9508)
Sum of squares = (1.002\2\ + 0.9675\2\) = 1.94
Sum of squares = (1.004\2\ + 0.9859\2\) = 1.98
Sum of squares = (1.006\2\ + 0.9940\2\) = 2.00
Sum of squares = (1.008\2\ + 0.9508\2\) = 1.92
[GRAPHIC] [TIFF OMITTED] TR19FE15.022

    (2) For engines with a high-speed governor that will be subject to a 
reference duty cycle that specifies normalized speeds greater than 100%, 
calculate an alternate maximum test speed, fntest,alt, as 
specified in this paragraph (a)(2). If fntest,alt is less 
than the measured maximum test speed, fntest, determined in 
paragraph (a)(1) of this section, replace fntest with 
fntest,alt. In this case, fntest,alt becomes the 
``maximum test speed'' for that engine. Note that Sec. 1065.510 allows 
you to apply an optional declared maximum test speed to

[[Page 177]]

the final measured maximum test speed determined as an outcome of the 
comparison between fntest, and fntest,alt in this 
paragraph (a)(2). Determine fntest,alt as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.160

Where:

fntest,alt = alternate maximum test speed
fnhi,idle = warm high-idle speed
fnidle = warm idle speed
% speedmax = maximum normalized speed from duty cycle
    Example: 
fnhi,idle = 2200 r/min
fnidle = 800 r/min
[GRAPHIC] [TIFF OMITTED] TR25OC16.161

fntest,alt = 2133 r/min

    (3) For variable-speed engines, transform normalized speeds to 
reference speeds according to paragraph (c) of this section by using the 
measured maximum test speed determined according to paragraphs (a)(1) 
and (2) of this section--or use your declared maximum test speed, as 
allowed in Sec. 1065.510.
    (4) For constant-speed engines, transform normalized speeds to 
reference speeds according to paragraph (c) of this section by using the 
measured no-load governed speed--or use your declared maximum test 
speed, as allowed in Sec. 1065.510.
    (b) Maximum test torque, Ttest. For constant-speed engines, 
determine the measured Ttest from the torque and power-
versus-speed maps, generated according to Sec. 1065.510, as follows:
    (1) For constant speed engines mapped using the methods in Sec. 
1065.510(d)(5)(i) or (ii), determine Ttest as follows:
    (i) Determine maximum power, Pmax, from the engine map 
generated according to Sec. 1065.510 and calculate the value for power 
equal to 98% of Pmax.
    (ii) Determine the lowest and highest engine speeds corresponding to 
98% of Pmax, using linear interpolation, and no 
extrapolation, as appropriate.
    (iii) Determine the engine speed corresponding to maximum power, 
fnPmax, by calculating the average of the two speed values 
from paragraph (a)(1)(ii) of this section. If there is only one speed 
where power is equal to 98% of Pmax, take fnPmax 
as the speed at which Pmax occurs.
    (iv) Transform the map into a normalized power-versus-speed map by 
dividing power terms by Pmax and dividing speed terms by 
fnPmax. Use Eq. 1065.610-1 to calculate a quantity 
representing the sum of squares from the normalized map.
    (v) Determine the maximum value for the sum of the squares from the 
map and multiply that value by 0.98.
    (vi) Determine the lowest and highest engine speeds corresponding to 
the value calculated in paragraph (a)(1)(v) of this section, using 
linear interpolation as appropriate. Calculate fntest as the 
average of these two speed values. If there is only one speed 
corresponding to the value calculated in paragraph (a)(1)(v) of this 
section, take fntest as the speed where the maximum of the 
sum of the squares occurs.

[[Page 178]]

    (vii) The measured Ttest is the mapped torque at 
fntest.
    (2) For constant-speed engines using the two-point mapping method in 
Sec. 1065.510(d)(5)(iii), you may follow paragraph (a)(1) of this 
section to determine the measured Ttest, or you may use the 
measured torque of the second point as the measured Ttest 
directly.
    (3) Transform normalized torques to reference torques according to 
paragraph (d) of this section by using the measured maximum test torque 
determined according to paragraph (b)(1) of this section--or use your 
declared maximum test torque, as allowed in Sec. 1065.510.
    (c) Generating reference speed values from normalized duty cycle 
speeds. Transform normalized speed values to reference values as 
follows:
    (1) % speed. If your normalized duty cycle specifies % speed values, 
use your warm idle speed and your maximum test speed to transform the 
duty cycle, as follows:


[GRAPHIC] [TIFF OMITTED] TR25OC16.162


    Example: 
% speed = 85% = 0.85
fntest = 2364 r/min
fnidle = 650 r/min
fnref = 0.85  (2364-650) + 650
fnref = 2107 r/min

    (2) A, B, and C speeds. If your normalized duty cycle specifies 
speeds as A, B, or C values, use your power-versus-speed curve to 
determine the lowest speed below maximum power at which 50% of maximum 
power occurs. Denote this value as nlo. Take nlo 
to be warm idle speed if all power points at speeds below the maximum 
power speed are higher than 50% of maximum power. Also determine the 
highest speed above maximum power at which 70% of maximum power occurs. 
Denote this value as nhi. If all power points at speeds above 
the maximum power speed are higher than 70% of maximum power, take 
nhi to be the declared maximum safe engine speed or the 
declared maximum representative engine speed, whichever is lower. Use 
nhi and nlo to calculate reference values for A, 
B, or C speeds as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.163

[GRAPHIC] [TIFF OMITTED] TR25OC16.164

[GRAPHIC] [TIFF OMITTED] TR25OC16.165

    Example: 
nlo = 1005 r/min
nhi = 2385 r/min
fnrefA = 0.25  (2385-1005) + 1005
fnrefB = 0.50  (2385-1005) + 1005
fnrefC = 0.75  (2385-1005) + 1005
fnrefA = 1350 r/min
fnrefB = 1695 r/min

[[Page 179]]

fnrefC = 2040 r/min

    (3) Intermediate speed. Based on the map, determine maximum torque, 
Tmax, and the corresponding speed, fnTmax, 
calculated as the average of the lowest and highest speeds at which 
torque is equal to 98% of Tmax. Use linear interpolation 
between points to determine the speeds where torque is equal to 98% of 
Tmax. Identify your reference intermediate speed as one of 
the following values:
    (i) fnTmax if it is between (60 and 75) % of maximum test 
speed.
    (ii) 60% of maximum test speed if fnTmax is less than 60% 
of maximum test speed.
    (iii) 75% of maximum test speed if fnTmax is greater than 
75% of maximum test speed.
    (d) Generating reference torques from normalized duty-cycle torques. 
Transform normalized torques to reference torques using your map of 
maximum torque versus speed.
    (1) Reference torque for variable-speed engines. For a given speed 
point, multiply the corresponding % torque by the maximum torque at that 
speed, according to your map. If your engine is subject to a reference 
duty cycle that specifies negative torque values (i.e., engine 
motoring), use negative torque for those motoring points (i.e., the 
motoring torque). If you map negative torque as allowed under Sec. 
1065.510 (c)(2) and the low-speed governor activates, resulting in 
positive torques, you may replace those positive motoring mapped torques 
with negative values between zero and the largest negative motoring 
torque. For both maximum and motoring torque maps, linearly interpolate 
mapped torque values to determine torque between mapped speeds. If the 
reference speed is below the minimum mapped speed (i.e., 95% of idle 
speed or 95% of lowest required speed, whichever is higher), use the 
mapped torque at the minimum mapped speed as the reference torque. The 
result is the reference torque for each speed point.
    (2) Reference torque for constant-speed engines. Multiply a % torque 
value by your maximum test torque. The result is the reference torque 
for each point.
    (3) Required deviations. We require the following deviations for 
variable-speed engines intended primarily for propulsion of a vehicle 
with an automatic transmission where that engine is subject to a 
transient duty cycle with idle operation. These deviations are intended 
to produce a more representative transient duty cycle for these 
applications. For steady-state duty cycles or transient duty cycles with 
no idle operation, these requirements do not apply. Idle points for 
steady state duty cycles of such engines are to be run at conditions 
simulating neutral or park on the transmission.
    (i) Zero-percent speed is the warm idle speed measured according to 
Sec. 1065.510(b)(6) with CITT applied, i.e., measured warm idle speed 
in drive.
    (ii) If the cycle begins with a set of contiguous idle points (zero-
percent speed, and zero-percent torque), leave the reference torques set 
to zero for this initial contiguous idle segment. This is to represent 
free idle operation with the transmission in neutral or park at the 
start of the transient duty cycle, after the engine is started. If the 
initial idle segment is longer than 24 seconds, change the reference 
torques for the remaining idle points in the initial contiguous idle 
segment to CITT (i.e., change idle points corresponding to 25 seconds to 
the end of the initial idle segment to CITT). This is to represent 
shifting the transmission to drive.
    (iii) For all other idle points, change the reference torque to 
CITT. This is to represent the transmission operating in drive.
    (iv) If the engine is intended primarily for automatic transmissions 
with a Neutral-When-Stationary feature that automatically shifts the 
transmission to neutral after the vehicle is stopped for a designated 
time and automatically shifts back to drive when the operator increases 
demand (i.e., pushes the accelerator pedal), change the reference torque 
back to zero for idle points in drive after the designated time.
    (v) For all points with normalized speed at or below zero percent 
and reference torque from zero to CITT, set the reference torque to 
CITT. This is to provide smoother torque references below idle speed.

[[Page 180]]

    (vi) For motoring points, make no changes.
    (vii) For consecutive points with reference torques from zero to 
CITT that immediately follow idle points, change their reference torques 
to CITT. This is to provide smooth torque transition out of idle 
operation. This does not apply if the Neutral-When-Stationary feature is 
used and the transmission has shifted to neutral.
    (viii) For consecutive points with reference torque from zero to 
CITT that immediately precede idle points, change their reference 
torques to CITT. This is to provide smooth torque transition into idle 
operation.
    (4) Permissible deviations for any engine. If your engine does not 
operate below a certain minimum torque under normal in-use conditions, 
you may use a declared minimum torque as the reference value instead of 
any value denormalized to be less than the declared value. For example, 
if your engine is connected to a hydrostatic transmission and it has a 
minimum torque even when all the driven hydraulic actuators and motors 
are stationary and the engine is at idle, then you may use this declared 
minimum torque as a reference torque value instead of any reference 
torque value generated under paragraph (d)(1) or (2) of this section 
that is between zero and this declared minimum torque.
    (e) Generating reference power values from normalized duty cycle 
powers. Transform normalized power values to reference speed and power 
values using your map of maximum power versus speed.
    (1) First transform normalized speed values into reference speed 
values. For a given speed point, multiply the corresponding % power by 
the mapped power at maximum test speed, fntest, unless 
specified otherwise by the standard-setting part. The result is the 
reference power for each speed point, Pref. Convert these 
reference powers to corresponding torques for operator demand and 
dynamometer control and for duty cycle validation per 1065.514. Use the 
reference speed associated with each reference power point for this 
conversion. As with cycles specified with % torque, linearly interpolate 
between these reference torque values generated from cycles with % 
power.
    (2) Permissible deviations for any engine. If your engine does not 
operate below a certain power under normal in-use conditions, you may 
use a declared minimum power as the reference value instead of any value 
denormalized to be less than the declared value. For example, if your 
engine is directly connected to a propeller, it may have a minimum power 
called idle power. In this case, you may use this declared minimum power 
as a reference power value instead of any reference power value 
generated per paragraph (e)(1) of this section that is from zero to this 
declared minimum power.

[73 FR 37324, June 30, 2008, as amended at 73 FR 59330, Oct. 8, 2008; 75 
FR 23045, Apr. 30, 2010; 76 FR 57453, Sept. 15, 2011; 78 FR 36398, June 
17, 2013; 79 FR 23783, Apr. 28, 2014; 80 FR 9118, Feb. 19, 2015; 81 FR 
74170, Oct. 25, 2016]



Sec. 1065.630  Local acceleration of gravity.

    (a) The acceleration of Earth's gravity, ag, varies 
depending on the test location. Determine ag at your location 
by entering latitude, longitude, and elevation data into the U.S. 
National Oceanographic and Atmospheric Administration's surface gravity 
prediction Web site at http://www.ngs.noaa.gov/cgi-bin/grav--pdx.prl.
    (b) If the Web site specified in paragraph (a) of this section is 
unavailable, you may calculate ag for your latitude as 
follows:
[GRAPHIC] [TIFF OMITTED] TR28AP14.143


[[Page 181]]


Where:

u = Degrees north or south latitude.

Example:

u = 45 deg.
ag = 9.7803267715 [middot] (1 + 5.2790414 [middot] 
          10-\3\ [middot] sin\2\ (45) + 2.32718 [middot] 
          10-\5\ [middot] sin\4\ (45) + 1.262 [middot] 
          10-\7\ [middot] sin\6\ (45) + 7 [middot] 
          10-\10\ [middot] sin\8\ (45)
ag = 9.8061992026 m/s \2\

[79 FR 23784, Apr. 28, 2014]



Sec. 1065.640  Flow meter calibration calculations.

    This section describes the calculations for calibrating various flow 
meters. After you calibrate a flow meter using these calculations, use 
the calculations described in Sec. 1065.642 to calculate flow during an 
emission test. Paragraph (a) of this section first describes how to 
convert reference flow meter outputs for use in the calibration 
equations, which are presented on a molar basis. The remaining 
paragraphs describe the calibration calculations that are specific to 
certain types of flow meters.
    (a) Reference meter conversions. The calibration equations in this 
section use molar flow rate, nref, as a reference quantity. 
If your reference meter outputs a flow rate in a different quantity, 
such as standard volume rate, vstdref, actual volume rate, 
vactref, or mass rate, mref, convert your 
reference meter output to a molar flow rate using the following 
equations, noting that while values for volume rate, mass rate, 
pressure, temperature, and molar mass may change during an emission 
test, you should ensure that they are as constant as practical for each 
individual set point during a flow meter calibration:
[GRAPHIC] [TIFF OMITTED] TR25OC16.166

Where:

nref = reference molar flow rate.
vstdref = reference volume flow rate, corrected to a standard 
          pressure and a standard temperature.
vactref = reference volume flow rate at the actual pressure 
          and temperature of the flow rate.
mref = reference mass flow.
pstd = standard pressure.
pact = actual pressure of the flow rate.
Tstd = standard temperature.
Tact = actual temperature of the flow rate.
R = molar gas constant.
Mmix = molar mass of the flow rate.
    Example 1: 
vstdref = 1000.00 ft\3\/min = 0.471948 m\3\/s
pstd = 29.9213 in Hg @32[emsp14]  deg.F = 101.325 kPa = 
          101325 Pa = 101325 kg/(m[micro]s\2\)
Tstd = 68.0[emsp14]  deg.F = 293.15 K
R = 8.314472 J/(mol[micro]K) = 8.314472 (m\2\[micro]kg)/
          (s\2\[micro]mol[micro]K)
          [GRAPHIC] [TIFF OMITTED] TR25OC16.167
          
nref = 19.619 mol/s

    Example 2: 
mref = 17.2683 kg/min = 287.805 g/s
Mmix = 28.7805 g/mol
[GRAPHIC] [TIFF OMITTED] TR25OC16.168


[[Page 182]]


nref = 10.0000 mol/s

    (b) PDP calibration calculations. Perform the following steps to 
calibrate a PDP flow meter:
    (1) Calculate PDP volume pumped per revolution, Vrev, for 
each restrictor position from the mean values determined in Sec. 
1065.340 as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.169

Where:

nref = mean reference molar flow rate.
R = molar gas constant.
Tin = mean temperature at the PDP inlet.
Pin = mean static absolute pressure at the PDP inlet.
fnPDP = mean PDP speed.
    Example: 
nref = 25.096 mol/s
R = 8.314472 J/(mol[micro]K) = 8.314472 (m\2\[micro]kg)/
          (s\2\[micro]mol[micro]K)
Tin = 299.5 K
Pin = 98.290 kPa = 98290 Pa = 98290 kg/(m[micro]s\2\)
fnPDP = 1205.1 r/min = 20.085 r/s
[GRAPHIC] [TIFF OMITTED] TR25OC16.170

Vrev = 0.03166 m\3\/r

    (2) Calculate a PDP slip correction factor, Ks, for each 
restrictor position from the mean values determined in Sec. 1065.340 as 
follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.171

Where:
fnPDP = mean PDP speed.
Pout = mean static absolute pressure at the PDP outlet.
Pin = mean static absolute pressure at the PDP inlet.
    Example: 
fnPDP = 1205.1 r/min = 20.085 r/s
Pout = 100.103 kPa
Pin = 98.290 kPa
[GRAPHIC] [TIFF OMITTED] TR25OC16.172


[[Page 183]]


Ks = 0.006700 s/r

    (3) Perform a least-squares regression of Vrev, versus 
Ks, by calculating slope, a1, and intercept, 
a0, as described in Sec. 1065.602.
    (4) Repeat the procedure in paragraphs (b)(1) through (3) of this 
section for every speed that you run your PDP.
    (5) The following table illustrates a range of typical values for 
different PDP speeds:

                           Table 1 of Sec. 1065.640--Example of PDP Calibration Data
----------------------------------------------------------------------------------------------------------------
                      fnPDP (revolution/s)                          a1 (m\3\/s)         a0 (m\3\/revolution)
----------------------------------------------------------------------------------------------------------------
12.6...........................................................              0.841                         0.056
16.5...........................................................              0.831                        -0.013
20.9...........................................................              0.809                         0.028
23.4...........................................................              0.788                        -0.061
----------------------------------------------------------------------------------------------------------------

    (6) For each speed at which you operate the PDP, use the appropriate 
regression equation from this paragraph (b) to calculate flow rate 
during emission testing as described in Sec. 1065.642.
    (c) Venturi governing equations and permissible assumptions. This 
section describes the governing equations and permissible assumptions 
for calibrating a venturi and calculating flow using a venturi. Because 
a subsonic venturi (SSV) and a critical-flow venturi (CFV) both operate 
similarly, their governing equations are nearly the same, except for the 
equation describing their pressure ratio, r (i.e., rSSV 
versus rCFV). These governing equations assume one-
dimensional isentropic inviscid flow of an ideal gas. Paragraph (c)(5) 
of this section describes other assumptions that may apply. If good 
engineering judgment dictates that you account for gas compressibility, 
you may either use an appropriate equation of state to determine values 
of Z as a function of measured pressure and temperature, or you may 
develop your own calibration equations based on good engineering 
judgment. Note that the equation for the flow coefficient, 
Cf, is based on the ideal gas assumption that the isentropic 
exponent, g, is equal to the ratio of specific heats, Cp/
Cv. If good engineering judgment dictates using a real gas 
isentropic exponent, you may either use an appropriate equation of state 
to determine values of g as a function of measured pressures and 
temperatures, or you may develop your own calibration equations based on 
good engineering judgment.
    (1) Calculate molar flow rate, n, as follows:
    [GRAPHIC] [TIFF OMITTED] TR25OC16.173
    
Where:

    Cd = discharge coefficient, as determined in paragraph 
(c)(2) of this section.
    Cf = flow coefficient, as determined in paragraph (c)(3) 
of this section.
    At = venturi throat cross-sectional area.
    pin = venturi inlet absolute static pressure.
    Z = compressibility factor.
    Mmix = molar mass of gas mixture.
    R = molar gas constant.
    Tin = venturi inlet absolute temperature.

    (2) Using the data collected in Sec. 1065.340, calculate 
Cd for each flow rate using the following equation:

[[Page 184]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.174

Where:

nref = a reference molar flow rate.

    (3) Determine Cf using one of the following methods:
    (i) For CFV flow meters only, determine CfCFV from the 
following table based on your values for b  and g , using linear 
interpolation to find intermediate values:

   Table 2 of Sec. 1065.640-CfCFV Versus b and g for CFV Flow Meters
------------------------------------------------------------------------
                                  CfCFV
-------------------------------------------------------------------------
                                                    gdexh = gair = 399
           b                    gexh = 385
------------------------------------------------------------------------
            0.000                   0.6822                  0.6846
            0.400                   0.6857                  0.6881
            0.500                   0.6910                  0.6934
            0.550                   0.6953                  0.6977
            0.600                   0.7011                  0.7036
            0.625                   0.7047                  0.7072
            0.650                   0.7089                  0.7114
            0.675                   0.7137                  0.7163
            0.700                   0.7193                  0.7219
            0.720                   0.7245                  0.7271
            0.740                   0.7303                  0.7329
            0.760                   0.7368                  0.7395
            0.770                   0.7404                  0.7431
            0.780                   0.7442                  0.7470
            0.790                   0.7483                  0.7511
            0.800                   0.7527                  0.7555
            0.810                   0.7573                  0.7602
            0.820                   0.7624                  0.7652
            0.830                   0.7677                  0.7707
            0.840                   0.7735                  0.7765
            0.850                   0.7798                  0.7828
------------------------------------------------------------------------

    (ii) For any CFV or SSV flow meter, you may use the following 
equation to calculate Cf for each flow rate:
[GRAPHIC] [TIFF OMITTED] TR25OC16.175

Where:

g = isentropic exponent. For an ideal gas, this is the ratio of specific 
          heats of the gas mixture, Cp/Cv.
r = pressure ratio, as determined in paragraph (c)(4) of this section.
b = ratio of venturi throat to inlet diameters.

    (4) Calculate r as follows:
    (i) For SSV systems only, calculate rSSV using the 
following equation:

[[Page 185]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.176

Where:

DpSSV = Differential static pressure; venturi inlet minus 
          venturi throat.

    (ii) For CFV systems only, calculate rCFV iteratively 
using the following equation:
[GRAPHIC] [TIFF OMITTED] TR25OC16.177

    (5) You may apply any of the following simplifying assumptions or 
develop other values as appropriate for your test configuration, 
consistent with good engineering judgment:
    (i) For raw exhaust, diluted exhaust, and dilution air, you may 
assume that the gas mixture behaves as an ideal gas: Z = 1.
    (ii) For raw exhaust, you may assume g = 1.385.
    (iii) For diluted exhaust and dilution air, you may assume g = 
1.399.
    (iv) For diluted exhaust and dilution air, you may assume the molar 
mass of the mixture, Mmix, is a function only of the amount 
of water in the dilution air or calibration air, as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.178

Where:

Mair = molar mass of dry air.
xH2O = amount of H2O in the dilution air or 
          calibration air, determined as described in Sec. 1065.645.
MH2O = molar mass of water.

    Example: 
Mair = 28.96559 g/mol
xH2O = 0.0169 mol/mol
MH2O = 18.01528 g/mol
Mmix = 28.96559 [middot] (1- 0.0169) + 18.01528 [middot] 
          0.0169
Mmix = 28.7805 g/mol

    (v) For diluted exhaust and dilution air, you may assume a constant 
molar mass of the mixture, Mmix, for all calibration and all 
testing as long as your assumed molar mass differs no more than [1% from 
the estimated minimum and maximum molar mass during calibration and 
testing.
    You may assume this, using good engineering judgment, if you 
sufficiently control the amount of water in calibration air and in 
dilution air or if you remove sufficient water from both calibration air 
and dilution air. The following table gives examples of permissible 
ranges of dilution air dewpoint versus calibration air dewpoint:

[[Page 186]]



  Table 3 of Sec. 1065.640--Examples of Dilution Air and Calibration Air Dewpoints at Which You May Assume a
                                                  Constant Mmix
----------------------------------------------------------------------------------------------------------------
                                                                     assume the
                                                                     following       for the following ranges of
               If calibration Tdew ( C) is . . .                 constant Mmix (g/    Tdew ( C) during emission
                                                                     mol) . . .               tests \a\
----------------------------------------------------------------------------------------------------------------
dry............................................................           28.96559                     dry to 18
0..............................................................           28.89263                     dry to 21
5..............................................................           28.86148                     dry to 22
10.............................................................           28.81911                     dry to 24
15.............................................................           28.76224                     dry to 26
20.............................................................           28.68685                      -8 to 28
25.............................................................           28.58806                      12 to 31
30.............................................................           28.46005                      23 to 34
----------------------------------------------------------------------------------------------------------------
\a\ Range valid for all calibration and emission testing over the atmospheric pressure range (80.000 to 103.325)
  kPa.

    (6) The following example illustrates the use of the governing 
equations to calculate Cd of an SSV flow meter at one 
reference flow meter value. Note that calculating Cd for a 
CFV flow meter would be similar, except that Cf would be 
determined from Table 2 of this section or calculated iteratively using 
values of b and g as described in paragraph (c)(2) of this section.

    Example: 
nref = 57.625 mol/s
Z = 1
Mmix = 28.7805 g/mol = 0.0287805 kg/mol
R = 8.314472 J/(mol [middot] K) = 8.314472 (m\2\ [middot] kg)/(s\2\ 
          [middot] mol [middot] K)
Tin = 298.15 K
At = 0.01824 m\2\
pin = 99.132 kPa = 99132.0 Pa = 99132 kg/(m[micro]s\2\)
g = 1.399
b = 0.8
Dp = 2.312 kPa
[GRAPHIC] [TIFF OMITTED] TR25OC16.179

Cf = 0.274
[GRAPHIC] [TIFF OMITTED] TR25OC16.314

Cd = 0.982

    (d) SSV calibration. Perform the following steps to calibrate an SSV 
flow meter:
    (1) Calculate the Reynolds number, Re#, for each 
reference molar flow rate, nref, using the throat diameter of 
the venturi, dt. Because the dynamic viscosity, m, is needed 
to compute Re#, you may use your own fluid viscosity model to 
determine m for your calibration gas (usually air), using good 
engineering judgment. Alternatively, you may use the Sutherland three-
coefficient viscosity model to approximate m, as shown in the following 
sample calculation for Re#:

[[Page 187]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.315

    Where, using the Sutherland three-coefficient viscosity model:
    [GRAPHIC] [TIFF OMITTED] TR25OC16.180
    
Where:

m[iheIO] = Sutherland reference viscosity.
T[iheIO] = Sutherland reference temperature.
S = Sutherland constant.

                                  Table 4 of Sec. 1065.640-- Sutherland Three-Coefficient Viscosity Model Parameters
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                              m[iheIO]         T[iheIO]            S         Temperature range within [         Pressure limit \b\
                                         ---------------------------------------------------        2% error \b\        --------------------------------
                 Gas \a\                                                                    ----------------------------
                                           kg/(m[micro]s)         K                K                      K                            kPa
--------------------------------------------------------------------------------------------------------------------------------------------------------
Air.....................................   1.716 [middot]              273              111  170 to 1900...............  <= 1800
                                                   10-\5\
CO[ihel2]...............................   1.370 [middot]              273              222  190 to 1700...............  <= 3600
                                                   10-\5\
H[ihel2]................................    1.12 [middot]              350             1064  360 to 1500...............  <= 10000
                                                   10-\5\
O[ihel2]................................   1.919 [middot]              273              139  190 to 2000...............  <= 2500
                                                   10-\5\
N[ihel2]................................   1.663 [middot]              273              107  100 to 1500...............  <= 1600
                                                   10-\5\
--------------------------------------------------------------------------------------------------------------------------------------------------------
\a\ Use tabulated parameters only for the pure gases, as listed. Do not combine parameters in calculations to calculate viscosities of gas mixtures.
\b\ The model results are valid only for ambient conditions in the specified ranges.

    Example: 
m0 = 1.716 [middot] 10-\5\ kg/(m[micro]s)
T[iheIO] = 273 K
S = 111 K
[GRAPHIC] [TIFF OMITTED] TR25OC16.181

[micro]  = 1.838 [middot] 10-5 kg/(m[micro]s)
Mmix = 28.7805 g/mol
nref = 57.625 mol/s
dt = 152.4 mm = 0.1524 m
Tin = 298.15 K
[GRAPHIC] [TIFF OMITTED] TR25OC16.182


[[Page 188]]


Re# = 7.538[micro]10\8\

    (2) Create an equation for Cd as a function of 
Re#, using paired values of the two quantities. The equation 
may involve any mathematical expression, including a polynomial or a 
power series. The following equation is an example of a commonly used 
mathematical expression for relating Cd and Re#:
[GRAPHIC] [TIFF OMITTED] TR25OC16.183

    (3) Perform a least-squares regression analysis to determine the 
best-fit coefficients for the equation and calculate SEE as described in 
Sec. 1065.602.
    (4) If the equation meets the criterion of SEE <= 0.5% [middot] 
Cdmax, you may use the equation for the corresponding range 
of Re#, as described in Sec. 1065.642.
    (5) If the equation does not meet the specified statistical 
criterion, you may use good engineering judgment to omit calibration 
data points; however you must use at least seven calibration data points 
to demonstrate that you meet the criterion. For example, this may 
involve narrowing the range of flow rates for a better curve fit.
    (6) Take corrective action if the equation does not meet the 
specified statistical criterion even after omitting calibration data 
points. For example, select another mathematical expression for the 
Cd versus Re# equation, check for leaks, or repeat 
the calibration process. If you must repeat the calibration process, we 
recommend applying tighter tolerances to measurements and allowing more 
time for flows to stabilize.
    (7) Once you have an equation that meets the specified statistical 
criterion, you may use the equation only for the corresponding range of 
Re#.
    (e) CFV calibration. Some CFV flow meters consist of a single 
venturi and some consist of multiple venturis, where different 
combinations of venturis are used to meter different flow rates. For CFV 
flow meters that consist of multiple venturis, either calibrate each 
venturi independently to determine a separate discharge coefficient, 
Cd, for each venturi, or calibrate each combination of 
venturis as one venturi. In the case where you calibrate a combination 
of venturis, use the sum of the active venturi throat areas as 
At, the square root of the sum of the squares of the active 
venturi throat diameters as dt, and the ratio of the venturi 
throat to inlet diameters as the ratio of the square root of the sum of 
the active venturi throat diameters (dt) to the diameter of 
the common entrance to all the venturis. (D). To determine the 
Cd for a single venturi or a single combination of venturis, 
perform the following steps:
    (1) Use the data collected at each calibration set point to 
calculate an individual Cd for each point using Eq. 1065.640-
4.
    (2) Calculate the mean and standard deviation of all the 
Cd values according to Eqs. 1065.602-1 and 1065.602-2.
    (3) If the standard deviation of all the Cd values is 
less than or equal to 0.3% of the mean Cd, use the mean 
Cd in Eq. 1065.642-4, and use the CFV only up to the highest 
venturi pressure ratio, r, measured during calibration using the 
following equation:

[[Page 189]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.184

Where:

DpCFV = Differential static pressure; venturi inlet minus 
          venturi outlet.

    (4) If the standard deviation of all the Cd values 
exceeds 0.3% of the mean Cd, omit the Cd value 
corresponding to the data point collected at the highest r measured 
during calibration.
    (5) If the number of remaining data points is less than seven, take 
corrective action by checking your calibration data or repeating the 
calibration process. If you repeat the calibration process, we recommend 
checking for leaks, applying tighter tolerances to measurements and 
allowing more time for flows to stabilize.
    (6) If the number of remaining Cd values is seven or 
greater, recalculate the mean and standard deviation of the remaining 
Cd values.
    (7) If the standard deviation of the remaining Cd values 
is less than or equal to 0.3% of the mean of the remaining 
Cd, use that mean Cd in Eq. 1065.642-4, and use 
the CFV values only up to the highest r associated with the remaining 
Cd.
    (8) If the standard deviation of the remaining Cd still 
exceeds 0.3% of the mean of the remaining Cd values, repeat 
the steps in paragraph (e)(4) through (8) of this section.

[79 FR 23785, Apr. 28, 2014, as amended at 81 FR 74172, Oct. 25, 2016]



Sec. 1065.642  PDP, SSV, and CFV molar flow rate calculations.

    This section describes the equations for calculating molar flow 
rates from various flow meters. After you calibrate a flow meter 
according to Sec. 1065.640, use the calculations described in this 
section to calculate flow during an emission test.
    (a) PDP molar flow rate. (1) Based on the speed at which you operate 
the PDP for a test interval, select the corresponding slope, 
a1, and intercept, a0, as calculated in Sec. 
1065.640, to calculate PDP molar flow rate,, as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.185

Where:

fnPDP = pump speed.
Vrev = PDP volume pumped per revolution, as determined in 
          paragraph (a)(2) of this section.
pin = static absolute pressure at the PDP inlet.
R = molar gas constant.
Tin = absolute temperature at the PDP inlet.

    (2) Calculate Vrev using the following equation:

[[Page 190]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.186

pout = static absolute pressure at the PDP outlet.
    Example: 
a1 = 0.8405 (m\3\/s)
fnPDP = 12.58 r/s
Pout = 99.950 kPa
Pin = 98.575 kPa = 98575 Pa = 98575 kg/(m[micro]s\2\)
a0 = 0.056 (m\3\/r)
R = 8.314472 J/(mol[micro]K) = 8.314472 (m\2\[micro]kg)/
          (s\2\[micro]mol[micro]K)
Tin = 323.5 K
[GRAPHIC] [TIFF OMITTED] TR25OC16.187

[GRAPHIC] [TIFF OMITTED] TR25OC16.188

n = 29.428 mol/s

    (b) SSV molar flow rate. Calculate SSV molar flow rate, n, as 
follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.316

Where:

Cd = discharge coefficient, as determined based on the 
          Cd versus Re# equation in Sec. 
          1065.640(d)(2).
Cf = flow coefficient, as determined in Sec. 
          1065.640(c)(2)(ii).
At = venturi throat cross-sectional area.
Pin = static absolute pressure at the venturi inlet.
Z = compressibility factor.
Mmix = molar mass of gas mixture.
R = molar gas constant.
Tin = absolute temperature at the venturi inlet.

    Example: 
At = 0.01824 m\2\
pin = 99.132 kPa = 99132 Pa = 99132 kg/(m[micro]s\2\)
Z = 1
Mmix = 28.7805 g/mol = 0.0287805 kg/mol
R = 8.314472 J/(mol[micro]K) = 8.314472 (m\2\[micro]kg)/
          (s\2\[micro]mol[micro]K)
Tin = 298.15 K
Re# = 7.232[micro]10\5\
g = 1.399
b = 0.8
Dp = 2.312 kPa

    Using Eq. 1065.640-7, rssv = 0.997

    Using Eq. 1065.640-6, Cf = 0.274

    Using Eq. 1065.640-5, Cd = 0.990

[[Page 191]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.189

n = 58.173 mol/s

    (c) CFV molar flow rate. If you use multiple venturis and you 
calibrate each venturi independently to determine a separate discharge 
coefficient, Cd (or calibration coefficient, Kv), 
for each venturi, calculate the individual molar flow rates through each 
venturi and sum all their flow rates to determine CFV flow rate, n. If 
you use multiple venturis and you calibrated venturis in combination, 
calculate n using the sum of the active venturi throat areas as 
At, the square root of the sum of the squares of the active 
venturi throat diameters as dt, and the ratio of the venturi 
throat to inlet diameters as the ratio of the square root of the sum of 
the active venturi throat diameters (dt) to the diameter of 
the common entrance to all the venturis (D).
    (1) To calculate n through one venturi or one combination of 
venturis, use its respective mean Cd and other constants you 
determined according to Sec. 1065.640 and calculate n as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.190

    Example: 
Cd = 0.985
Cf = 0.7219
At = 0.00456 m\2\
pin = 98.836 kPa = 98836 Pa = 98836 kg/(m[micro]s\2\)
Z = 1
Mmix = 28.7805 g/mol = 0.0287805 kg/mol
R = 8.314472 J/(mol[micro]K) = 8.314472 (m\2\[micro]kg)/
          (s\2\[micro]mol[micro]K)
Tin = 378.15 K
[GRAPHIC] [TIFF OMITTED] TR25OC16.191

n = 33.690 mol/s

    (2) To calculate the molar flow rate through one venturi or a 
combination of venturis, you may use its respective mean, Kv, 
and other constants you determined according to Sec. 1065.640 and 
calculate its molar flow rate n during an emission test. Note that if 
you follow the permissible ranges of dilution air dewpoint versus 
calibration air dewpoint in Table 3 of Sec. 1065.640, you may set 
Mmix-cal and Mmix equal to 1. Calculate n as 
follows:

[[Page 192]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.192

Where:
[GRAPHIC] [TIFF OMITTED] TR25OC16.193

Vstdref = volume flow rate of the standard at reference 
          conditions of 293.15 K and 101.325 kPa.
Tin-cal = venturi inlet temperature during calibration.
Pin-cal = venturi inlet pressure during calibration.
Mmix-cal = molar mass of gas mixture used during calibration.
Mmix = molar mass of gas mixture during the emission test 
          calculated using Eq. 1065.640-9.

    Example: 
Vstdref = 0.4895 m\3\
Tin-cal = 302.52 K
Pin-cal = 99.654 kPa = 99654 Pa = 99654 kg/(m[micro]s\2\)
pin = 98.836 kPa = 98836 Pa = 98836 kg/(m[micro]s\2\)
pstd = 101.325 kPa = 101325 Pa = 101325 kg/(m[micro]s\2\)
Mmix-cal = 28.9656 g/mol = 0.0289656 kg/mol
Mmix = 28.7805 g/mol = 0.0287805 kg/mol
Tin = 353.15 K
Tstd = 293.15 K
R = 8.314472 J/(mol[micro]K) = 8.314472 (m\2\[micro]kg)/
          (s\2\[micro]mol[micro]K)
          [GRAPHIC] [TIFF OMITTED] TR25OC16.194
          
n = 16.457 mol/s

[81 FR 74177, Oct. 25, 2016]



Sec. 1065.644  Vacuum-decay leak rate.

    This section describes how to calculate the leak rate of a vacuum-
decay leak verification, which is described in Sec. 1065.345(e). Use 
the following equation to calculate the leak rate nleak, and 
compare it to the criterion specified in Sec. 1065.345(e):

[[Page 193]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.036

Where:

Vvac = geometric volume of the vacuum-side of the sampling 
          system.
R = molar gas constant.
p2 = vacuum-side absolute pressure at time t2.
T2 = vacuum-side absolute temperature at time t2.
p1 = vacuum-side absolute pressure at time t1.
T1 = vacuum-side absolute temperature at time t1.
t2 = time at completion of vacuum-decay leak verification 
          test.
t1 = time at start of vacuum-decay leak verification test.

Example:

Vvac = 2.0000 L = 0.00200 m\3\
R = 8.314472 J/(mol [middot] K) = 8.314472 (m\2\ [middot] kg)/(s\2\ 
          [middot] mol [middot] K)
p2 = 50.600 kPa = 50600 Pa = 50600 kg/(m [middot] s\2\)
T2 = 293.15 K
p1 = 25.300 kPa = 25300 Pa = 25300 kg/(m [middot] s\2\)
T1 = 293.15 K
t2 = 10:57:35 a.m.
t1 = 10:56:25 a.m.
[GRAPHIC] [TIFF OMITTED] TR28AP14.037

[GRAPHIC] [TIFF OMITTED] TR28AP14.038


[79 FR 23795, Apr. 28, 2014]



Sec. 1065.645  Amount of water in an ideal gas.

    This section describes how to determine the amount of water in an 
ideal gas, which you need for various performance verifications and 
emission calculations. Use the equation for the vapor pressure of water 
in paragraph (a) of this section or another appropriate equation and, 
depending on whether you measure dewpoint or relative humidity, perform 
one of the calculations in paragraph (b) or (c) of this section. 
Paragraph (d) of this section provides an equation for determining 
dewpoint from relative humidity and dry bulb temperature measurements. 
The equations for the vapor pressure of water as presented in this 
section are derived from equations in ``Saturation Pressure of Water on 
the New Kelvin Temperature Scale'' (Goff, J.A., Transactions American 
Society of Heating and Air-Conditioning Engineers, Vol. 63, No. 1607, 
pages 347-354). Note that the equations were originally published to 
derive vapor pressure in units of atmospheres and have been modified to 
derive results in units of kPa by converting the last term in each 
equation.
    (a) Vapor pressure of water. Calculate the vapor pressure of water 
for a given saturation temperature condition, Tsat, as 
follows, or use good engineering judgment to use a different 
relationship of the vapor pressure of water to a

[[Page 194]]

given saturation temperature condition:
    (1) For humidity measurements made at ambient temperatures from (0 
to 100)  deg.C, or for humidity measurements made over super-cooled 
water at ambient temperatures from (-50 to 0)  deg.C, use the following 
equation:
[GRAPHIC] [TIFF OMITTED] TR28AP14.039

    (2) For humidity measurements over ice at ambient temperatures from 
(-100 to 0)  deg.C, use the following equation:

[[Page 195]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.040

    (b) Dewpoint. If you measure humidity as a dewpoint, determine the 
amount of water in an ideal gas, xH20, as follows:
[GRAPHIC] [TIFF OMITTED] TR30AP10.034

Where:

xH20 = amount of water in an ideal gas.
pH20 = water vapor pressure at the measured dewpoint, 
          Tsat = Tdew.
pabs = wet static absolute pressure at the location of your 
          dewpoint measurement.

Example::

pabs = 99.980 kPa
Tsat = Tdew = 9.5  deg.C
Using Eq. 1065.645-1,
pH20 = 1.186581 kPa
xH2O = 1.186581/99.980
xH2O = 0.011868 mol/mol

    (c) Relative humidity. If you measure humidity as a relative 
humidity, RH, determine the amount of water in an ideal gas, 
xH2O, as follows:

[[Page 196]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.195

Where:

xH2O = amount of water in an ideal gas.
RH = relative humidity.
pH2O = water vapor pressure at 100% relative humidity at the 
          location of your relative humidity measurement, 
          Tsat = Tamb.
pabs = wet static absolute pressure at the location of your 
          relative humidity measurement.

    Example: 
RH = 50.77% = 0.5077
pabs = 99.980 kPa
Tsat = Tamb = 20  deg.C
    Using Eq. 1065.645-1,
pH2O = 2.3371 kPa
xH2O = (0.5077 [middot] 2.3371)/99.980
xH2O = 0.011868 mol/mol

    (d) Dewpoint determination from relative humidity and dry bulb 
temperature. This paragraph (d) describes how to calculate dewpoint 
temperature from relative humidity, RH. This is based on ``ITS-90 
Formulations for Vapor Pressure, Frostpoint Temperature, Dewpoint 
Temperature, and Enhancement Factors in the Range -100 to + 100  deg.C'' 
(Hardy, B., The Proceedings of the Third International Symposium on 
Humidity & Moisture, Teddington, London, England, April 1998). Calculate 
pH20sat as described in paragraph (a) of this section based 
on setting Tsat equal to Tamb. Calculate 
pH20scaled by multiplying pH20sat by RH. Calculate 
the dewpoint, Tdew, from pH20 using the following 
equation:
[GRAPHIC] [TIFF OMITTED] TR25OC16.196

Where:

ln(pH2O) = the natural log of pH2Oscaled, which is 
          the water vapor pressure scaled to the relative humidity at 
          the location of the relative humidity measurement, 
          Tsat = Tamb

    Example: 
RH = 39.61% = 0.3961
Tsat = Tamb = 20.00  deg.C = 293.15K
    Using Eq. 1065.645-1,
pH2Osat = 2.3371 kPa
pH2Oscaled = (0.3961 [middot] 2.3371) = 0.925717 kPa = 
          925.717 Pa
          [GRAPHIC] [TIFF OMITTED] TR25OC16.197
          

[73 FR 37327, June 30, 2008, as amended at 73 FR 59331, Oct. 8, 2008; 75 
FR 23048, Apr. 30, 2010; 76 FR 57456, Sept. 15, 2011;79 FR 23796, Apr. 
28, 2014; 81 FR 74179, Oct. 25, 2016]



Sec. 1065.650  Emission calculations.

    (a) General. Calculate brake-specific emissions over each applicable 
duty cycle or test interval. For test intervals with zero work (or 
power), calculate the emission mass (or mass rate), but do not calculate 
brake-specific emissions. For duty cycles with multiple test intervals, 
refer to the standard-setting part for calculations you need to 
determine a composite result, such as a calculation that weights and 
sums the results of individual test

[[Page 197]]

intervals in a duty cycle. If the standard-setting part does not include 
those calculations, use the equations in paragraph (g) of this section. 
This section is written based on rectangular integration, where each 
indexed value (i.e., ``i'') represents (or approximates) the 
mean value of the parameter for its respective time interval, delta-t. 
You may also integrate continuous signals using trapezoidal integration 
consistent with good engineering judgment.
    (b) Brake-specific emissions over a test interval. We specify three 
alternative ways to calculate brake-specific emissions over a test 
interval, as follows:
    (1) For any testing, you may calculate the total mass of emissions, 
as described in paragraph (c) of this section, and divide it by the 
total work generated over the test interval, as described in paragraph 
(d) of this section, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR30AP10.036

Example:

mNOx = 64.975 g
W = 25.783 kW [middot] hr
eNOx = 64.975/25.783
eNOx = 2.520 g/(kW [middot] hr)

    (2) For discrete-mode steady-state testing, you may calculate the 
brake-specific emissions over a test interval using the ratio of 
emission mass rate to power, as described in paragraph (e) of this 
section, using the following equation:
[GRAPHIC] [TIFF OMITTED] TR30AP10.037

    (3) For field testing, you may calculate the ratio of total mass to 
total work, where these individual values are determined as described in 
paragraph (f) of this section. You may also use this approach for 
laboratory testing, consistent with good engineering judgment. Good 
engineering judgment dictates that this method not be used if there are 
any work flow paths described in Sec. 1065.210 that cross the system 
boundary, other than the primary output shaft (crankshaft). This is a 
special case in which you use a signal linearly proportional to raw 
exhaust molar flow rate to determine a value proportional to total 
emissions. You then use the same linearly proportional signal to 
determine total work using a chemical balance of fuel, intake air, and 
exhaust as described in Sec. 1065.655, plus information about your 
engine's brake-specific fuel consumption. Under this method, flow meters 
need not meet accuracy specifications, but they must meet the applicable 
linearity and repeatability specifications in subpart D or subpart J of 
this part. The result is a brake-specific emission value calculated as 
follows:
[GRAPHIC] [TIFF OMITTED] TR30AP10.038

Example:

m = 805.5 g

[[Page 198]]

W = 52.102 kW [middot] hr
eCO = 805.5/52.102
eCO = 2.520 g/(kW [middot] hr)

    (c) Total mass of emissions over a test interval. To calculate the 
total mass of an emission, multiply a concentration by its respective 
flow. For all systems, make preliminary calculations as described in 
paragraph (c)(1) of this section to correct concentrations. Next, use 
the method in paragraphs (c)(2) through (4) of this section that is 
appropriate for your system. Finally, if necessary, calculate the mass 
of NMHC as described in paragraph (c)(5) of this section for all 
systems. Calculate the total mass of emissions as follows:
    (1) Concentration corrections. Perform the following sequence of 
preliminary calculations on recorded concentrations:
    (i) Correct all gaseous emission analyzer concentration readings, 
including continuous readings, sample bag readings, and dilution air 
background readings, for drift as described in Sec. 1065.672. Note that 
you must omit this step where brake-specific emissions are calculated 
without the drift correction for performing the drift validation 
according to Sec. 1065.550(b). When applying the initial THC and 
CH4 contamination readings according to Sec. 1065.520(f), 
use the same values for both sets of calculations. You may also use as-
measured values in the initial set of calculations and corrected values 
in the drift-corrected set of calculations as described in Sec. 
1065.520(f)(7).
    (ii) Correct all THC and CH4 concentrations for initial 
contamination as described in Sec. 1065.660(a), including continuous 
readings, sample bags readings, and dilution air background readings.
    (iii) Correct all concentrations measured on a ``dry'' basis to a 
``wet'' basis, including dilution air background concentrations, as 
described in Sec. 1065.659.
    (iv) Calculate all NMHC and CH4 concentrations, including 
dilution air background concentrations, as described in Sec. 1065.660.
    (v) For emission testing with an oxygenated fuel, calculate any HC 
concentrations, including dilution air background concentrations, as 
described in Sec. 1065.665. See subpart I of this part for testing with 
oxygenated fuels.
    (vi) Correct all the NOX concentrations, including 
dilution air background concentrations, for intake-air humidity as 
described in Sec. 1065.670.
    (2) Continuous sampling. For continuous sampling, you must 
frequently record a continuously updated concentration signal. You may 
measure this concentration from a changing flow rate or a constant flow 
rate (including discrete-mode steady-state testing), as follows:
    (i) Varying flow rate. If you continuously sample from a changing 
exhaust flow rate, time align and then multiply concentration 
measurements by the flow rate from which you extracted it. Use good 
engineering judgment to time align flow and concentration data to match 
transformation time, t50, to within [1 s. We consider the 
following to be examples of changing flows that require a continuous 
multiplication of concentration times molar flow rate: Raw exhaust, 
exhaust diluted with a constant flow rate of dilution air, and CVS 
dilution with a CVS flowmeter that does not have an upstream heat 
exchanger or electronic flow control. This multiplication results in the 
flow rate of the emission itself. Integrate the emission flow rate over 
a test interval to determine the total emission. If the total emission 
is a molar quantity, convert this quantity to a mass by multiplying it 
by its molar mass, M. The result is the mass of the emission, m. 
Calculate m for continuous sampling with variable flow using the 
following equations:
[GRAPHIC] [TIFF OMITTED] TR08OC08.006

Where:

[[Page 199]]

[GRAPHIC] [TIFF OMITTED] TR08OC08.007

Example:

MNMHC = 13.875389 g/mol
N = 1200
xNMHC1 = 84.5 [micro] mol/mol = 84.5 [middot] 10-6 
          mol/mol
xNMHC2 = 86.0 [micro] mol/mol = 86.0 [middot] 10-6 
          mol/mol
nexh1 = 2.876 mol/s
nexh2 = 2.224 mol/s
frecord = 1 Hz

Using Eq. 1065.650-5,

Dt = 1/1 = 1 s
mNMHC = 13.875389 [middot] (84.5 [middot] 10-6 
          [middot] 2.876 + 86.0 [middot] 10-6 [middot] 2.224 
          + ... + xNMHC1200 [middot] nexh) 
          [middot] 1
mNMHC = 25.53 g

    (ii) Constant flow rate. If you continuously sample from a constant 
exhaust flow rate, use the same emission calculations described in 
paragraph (c)(2)(i) of this section or calculate the mean or flow-
weighted concentration recorded over the test interval and treat the 
mean as a batch sample, as described in paragraph (c)(3)(ii) of this 
section. We consider the following to be examples of constant exhaust 
flows: CVS diluted exhaust with a CVS flowmeter that has either an 
upstream heat exchanger, electronic flow control, or both.
    (3) Batch sampling. For batch sampling, the concentration is a 
single value from a proportionally extracted batch sample (such as a 
bag, filter, impinger, or cartridge). In this case, multiply the mean 
concentration of the batch sample by the total flow from which the 
sample was extracted. You may calculate total flow by integrating a 
changing flow rate or by determining the mean of a constant flow rate, 
as follows:
    (i) Varying flow rate. If you collect a batch sample from a changing 
exhaust flow rate, extract a sample proportional to the changing exhaust 
flow rate. We consider the following to be examples of changing flows 
that require proportional sampling: Raw exhaust, exhaust diluted with a 
constant flow rate of dilution air, and CVS dilution with a CVS 
flowmeter that does not have an upstream heat exchanger or electronic 
flow control. Integrate the flow rate over a test interval to determine 
the total flow from which you extracted the proportional sample. 
Multiply the mean concentration of the batch sample by the total flow 
from which the sample was extracted. If the total emission is a molar 
quantity, convert this quantity to a mass by multiplying it by its molar 
mass, M. The result is the mass of the emission, m. In the case of PM 
emissions, where the mean PM concentration is already in units of mass 
per mole of sample, MPM, simply multiply it by the total 
flow. The result is the total mass of PM, mPM. Calculate m 
for batch sampling with variable flow using the following equation:
[GRAPHIC] [TIFF OMITTED] TR06MY08.040

Example:

MNOx = 46.0055 g/mol
N = 9000
xNOx = 85.6 [micro] mol/mol = 85.6 [middot] 10-6 
          mol/mol
ndexh1 = 25.534 mol/s
ndexh2 = 26.950 mol/s
frecord = 5 Hz

Using Eq. 1065.650-5,

Dt = 1/5 = 0.2
mNOx = 46.0055 [middot] 85.6 [middot] 10-6 
          [middot] (25.534 + 26.950 + ... + nexh9000) 
          [middot] 0.2
mNOx = 4.201 g

    (ii) Constant flow rate. If you batch sample from a constant exhaust 
flow rate, extract a sample at a proportional or constant flow rate. We 
consider the following to be examples of constant exhaust flows: CVS 
diluted exhaust with a CVS flow meter that has either an upstream heat 
exchanger, electronic flow control, or both. Determine the mean molar 
flow rate from which you extracted the constant flow rate sample. 
Multiply the mean concentration of the batch sample by the mean molar 
flow rate of the exhaust from which the sample was extracted, and 
multiply the result by the time of the test interval. If the total 
emission is a molar quantity, convert this quantity to a mass by 
multiplying it by its molar mass, M. The result is the mass of the 
emission, m. In the case of PM emissions, where the mean PM 
concentration is already in units of mass

[[Page 200]]

per mole of sample, MPM, simply multiply it by the total 
flow, and the result is the total mass of PM, mPM. Calculate 
m for sampling with constant flow using the following equations:
[GRAPHIC] [TIFF OMITTED] TR06MY08.041


and for PM or any other analysis of a batch sample that yields a mass 
per mole of sample,
[GRAPHIC] [TIFF OMITTED] TR06MY08.042

Example:

MPM = 144.0 [micro] g/mol = 144.0 [middot] 10-6 g/
          mol
ndexh = 57.692 mol/s
Dt = 1200 s
mPM = 144.0 [middot] 10-6 [middot] 57.692 [middot] 
          1200
mPM = 9.9692 g

    (4) Additional provisions for diluted exhaust sampling; continuous 
or batch. The following additional provisions apply for sampling 
emissions from diluted exhaust:
    (i) For sampling with a constant dilution ratio, DR, of diluted 
exhaust versus exhaust flow (e.g., secondary dilution for PM sampling), 
calculate m using the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.044

Example:

mPMdil = 6.853 g
DR = 6:1
mPM = 6.853 [middot] 6
mPM = 41.118 g

    (ii) For continuous or batch sampling, you may measure background 
emissions in the dilution air. You may then subtract the measured 
background emissions, as described in Sec. 1065.667.
    (5) Mass of NMHC. Compare the corrected mass of NMHC to corrected 
mass of THC. If the corrected mass of NMHC is greater than 0.98 times 
the corrected mass of THC, take the corrected mass of NMHC to be 0.98 
times the corrected mass of THC. If you omit the NMHC calculations as 
described in Sec. 1065.660(b)(1), take the corrected mass of NMHC to be 
0.98 times the corrected mass of THC.
    (6) Mass of NMNEHC. If the test fuel has less than 0.010 mol/mol of 
ethane and you omit the NMNEHC calculations as described in Sec. 
1065.660(c)(1), take the corrected mass of NMNEHC to be 0.95 times the 
corrected mass of NMHC.
    (d) Total work over a test interval. To calculate the total work 
from the engine over a test interval, add the total work from all the 
work paths described in Sec. 1065.210 that cross the system boundary 
including electrical energy/work, mechanical shaft work, and fluid 
pumping work. For all work paths, except the engine's primary output 
shaft (crankshaft), the total work for the path over the test interval 
is the integration of the net work flow rate (power) out of the system 
boundary. When energy/work flows into the system boundary, this work 
flow rate signal becomes negative; in this case, include these negative 
work rate values in the integration to calculate total work from that 
work path. Some work paths may result in a negative total work. Include 
negative total work values from any work path in the calculated total 
work from the engine rather than setting the values to zero. The rest of 
this paragraph (d) describes how to calculate total work from the 
engine's primary output shaft over a test interval. Before integrating 
power on the engine's primary output shaft, adjust the speed and torque 
data for the time alignment used in Sec. 1065.514(c). Any advance or 
delay used on the feedback signals for cycle validation must also be 
used for calculating work. Account for work of accessories according to 
Sec. 1065.110. Exclude any work during cranking and starting. Exclude 
work during actual motoring operation (negative feedback torques), 
unless the engine was connected to one or more energy storage devices. 
Examples of such

[[Page 201]]

energy storage devices include hybrid powertrain batteries and hydraulic 
accumulators, like the ones illustrated in Figure 1 of Sec. 1065.210. 
Exclude any work during reference zero-load idle periods (0% speed or 
idle speed with 0 N [middot] m reference torque). Note, that there must 
be two consecutive reference zero load idle points to establish a period 
where this applies. Include work during idle points with simulated 
minimum torque such as Curb Idle Transmissions Torque (CITT) for 
automatic transmissions in ``drive''. The work calculation method 
described in paragraphs (b)(1) through (7) of this section meets these 
requirements using rectangular integration. You may use other logic that 
gives equivalent results. For example, you may use a trapezoidal 
integration method as described in paragraph (b)(8) of this section.
    (1) Time align the recorded feedback speed and torque values by the 
amount used in Sec. 1065.514(c).
    (2) Calculate shaft power at each point during the test interval by 
multiplying all the recorded feedback engine speeds by their respective 
feedback torques.
    (3) Adjust (reduce) the shaft power values for accessories according 
to Sec. 1065.110.
    (4) Set all power values during any cranking or starting period to 
zero. See Sec. 1065.525 for more information about engine cranking.
    (5) Set all negative power values to zero, unless the engine was 
connected to one or more energy storage devices. If the engine was 
tested with an energy storage device, leave negative power values 
unaltered.
    (6) Set all power values to zero during idle periods with a 
corresponding reference torque of 0 N [middot] m.
    (7) Integrate the resulting values for power over the test interval. 
Calculate total work as follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.045

Where:

W = total work from the primary output shaft.
Pi = instantaneous power from the primary output shaft over 
          an interval i.
          [GRAPHIC] [TIFF OMITTED] TR15SE11.046
          
Where:

N = 9000
[fnof]n1 = 1800.2 r/min
[fnof]n2 = 1805.8 r/min
T1 = 177.23 N [middot] m
T2 = 175.00 N [middot] m
Crev = 2 [middot] p rad/r
Ct1 = 60 s/min
Cp = 1000 (N [middot] m [middot] rad/s)/kW
[fnof]record = 5 Hz
Ct2 = 3600 s/hr
[GRAPHIC] [TIFF OMITTED] TR15SE11.047


[[Page 202]]


P1 = 33.41 kW
P2 = 33.09 kW

Using Eq. 1065.650-5,

Dt = 1/5 = 0.2 s
[GRAPHIC] [TIFF OMITTED] TR15SE11.048

W = 16.875 kW [middot] hr

    (8) You may use a trapezoidal integration method instead of the 
rectangular integration described in this paragraph (d). To do this, you 
must integrate the fraction of work between points where the torque is 
positive. You may assume that speed and torque are linear between data 
points. You may not set negative values to zero before running the 
integration.
    (e) Steady-state mass rate divided by power. To determine steady-
state brake-specific emissions for a test interval as described in 
paragraph (b)(2) of this section, calculate the mean steady-state mass 
rate of the emission, mi, and the mean steady-state power, P as follows:
    (1) To calculate mi, multiply its mean concentration, x, by its 
corresponding mean molar flow rate, ni. If the result is a molar flow 
rate, convert this quantity to a mass rate by multiplying it by its 
molar mass, M. The result is the mean mass rate of the emission, mi. In 
the case of PM emissions, where the mean PM concentration is already in 
units of mass per mole of sample, MPM, simply multiply it by 
the mean molar flow rate, ni. The result is the mass rate of PM, 
mPM. Calculate mi using the following equation:
[GRAPHIC] [TIFF OMITTED] TR06MY08.048

    (2) To calculate an engine's mean steady-state total power, P, add 
the mean steady-state power from all the work paths described in Sec. 
1065.210 that cross the system boundary including electrical power, 
mechanical shaft power, and fluid pumping power. For all work paths, 
except the engine's primary output shaft (crankshaft), the mean steady-
state power over the test interval is the integration of the net work 
flow rate (power) out of the system boundary divided by the period of 
the test interval. When power flows into the system boundary, the power/
work flow rate signal becomes negative; in this case, include these 
negative power/work rate values in the integration to calculate the mean 
power from that work path. Some work paths may result in a negative mean 
power. Include negative mean power values from any work path in the mean 
total power from the engine rather than setting these values to zero. 
The rest of this paragraph (e)(2) describes how to calculate the mean 
power from the engine's primary output shaft. Calculate P using Eq. 
1065.650-13, noting that P, fn, and T refer to mean power, 
mean rotational shaft frequency, and mean torque from the primary output 
shaft. Account for the power of simulated accessories according to Sec. 
1065.110 (reducing the mean primary output shaft power or torque by the 
accessory power or torque). Set the power to zero during actual motoring 
operation (negative feedback torques), unless the engine was connected 
to one or more energy storage devices. Examples of such energy storage 
devices include hybrid powertrain batteries and hydraulic accumulators, 
like the ones illustrated in Figure 1 of Sec. 1065.210. Set the power 
to zero for modes with a zero reference load (0 N[micro]m reference 
torque or 0 kW reference power). Include power during idle modes with 
simulated minimum torque or power.

[[Page 203]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.198

    (3) Divide emission mass rate by power to calculate a brake-specific 
emission result as described in paragraph (b)(2) of this section.
    (4) The following example shows how to calculate mass of emissions 
using mean mass rate and mean power:

MCO = 28.0101 g/mol
xCO = 12.00 mmol/mol = 0.01200 mol/mol
ni = 1.530 mol/s
fn = 3584.5 r/min = 375.37 rad/s
T = 121.50 N [middot] m
mi = 28.0101 [middot] 0.01200 [middot] 1.530
mi = 0.514 g/s = 1850.4 g/hr
P = 121.5 [middot] 375.37
P = 45607 W
P = 45.607 kW
eCO = 1850.4/45.61
eCO = 40.57 g/(kW [middot] hr)

    (f) Ratio of total mass of emissions to total work. To determine 
brake-specific emissions for a test interval as described in paragraph 
(b)(3) of this section, calculate a value proportional to the total mass 
of each emission. Divide each proportional value by a value that is 
similarly proportional to total work.
    (1) Total mass. To determine a value proportional to the total mass 
of an emission, determine total mass as described in paragraph (c) of 
this section, except substitute for the molar flow rate, n, or the total 
flow, n, with a signal that is linearly proportional to molar flow rate, 
nj, or linearly proportional to total flow, n as follows:
[GRAPHIC] [TIFF OMITTED] TR06MY08.050

    (2) Total work. To calculate a value proportional to total work over 
a test interval, integrate a value that is proportional to power. Use 
information about the brake-specific fuel consumption of your engine, 
efuel, to convert a signal proportional to fuel flow rate to 
a signal proportional to power. To determine a signal proportional to 
fuel flow rate, divide a signal that is proportional to the mass rate of 
carbon products by the fraction of carbon in your fuel, wC. 
You may use a measured wC or you may use default values for a 
given fuel as described in Sec. 1065.655(e). Calculate the mass rate of 
carbon from the amount of carbon and water in the exhaust, which you 
determine with a chemical balance of fuel, intake air, and exhaust as 
described in Sec. 1065.655. In the chemical balance, you must use 
concentrations from the flow that generated the signal proportional to 
molar flow rate, nj, in paragraph (e)(1) of this section. Calculate a 
value proportional to total work as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.199

Where:

[[Page 204]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.200

    (3) Brake-specific emissions. Divide the value proportional to total 
mass by the value proportional to total work to determine brake-specific 
emissions, as described in paragraph (b)(3) of this section.
    (4) Example: The following example shows how to calculate mass of 
emissions using proportional values:

N = 3000
[fnof]record = 5 Hz
efuel = 285 g/(kW[micro]hr)
wfuel = 0.869 g/g
MC = 12.0107 g/mol
nj1 = 3.922 mol/s = 14119.2 mol/hr
xCcombdry1 = 91.634 mmol/mol = 0.091634 mol/mol
xH2Oexh1 = 27.21 mmol/mol = 0.02721 mol/mol
    Using Eq. 1065.650-5,
Dt = 0.2 s
[GRAPHIC] [TIFF OMITTED] TR25OC16.201

W = 5.09 (kW[micro]hr)

    (g) Brake-specific emissions over a duty cycle with multiple test 
intervals. The standard-setting part may specify a duty cycle with 
multiple test intervals, such as with discrete-mode steady-state 
testing. Unless we specify otherwise, calculate composite brake-specific 
emissions over the duty cycle as described in this paragraph (g). If a 
measured mass (or mass rate) is negative, set it to zero for calculating 
composite brake-specific emissions, but leave it unchanged for drift 
validation. In the case of calculating composite brake-specific 
emissions relative to a combined emission standard (such as a 
NOX + NMHC standard), change any negative mass (or mass rate) 
values to zero for a particular pollutant before combining the values 
for the different pollutants.
    (1) Use the following equation to calculate composite brake-specific 
emissions for duty cycles with multiple test intervals all with 
prescribed durations, such as cold-start and hot-start transient cycles:
[GRAPHIC] [TIFF OMITTED] TR30AP10.045

Where:

i = test interval number.
N = number of test intervals.
WF = weighting factor for the test interval as defined in the standard-
          setting part.
m = mass of emissions over the test interval as determined in paragraph 
          (c) of this section.
W = total work from the engine over the test interval as determined in 
          paragraph (d) of this section.


[[Page 205]]


Example:

N = 2
WF1 = 0.1428
WF2 = 0.8572
m1 = 70.125 g
m2 = 64.975 g
W1 = 25.783 kW [middot] hr
W2 = 25.783 kW [middot] hr
[GRAPHIC] [TIFF OMITTED] TR30AP10.046

eNOxcomposite = 2.548 g/kW [middot] hr

    (2) Calculate composite brake-specific emissions for duty cycles 
with multiple test intervals that allow use of varying duration, such as 
discrete-mode steady-state duty cycles, as follows:
    (i) Use the following equation if you calculate brake-specific 
emissions over test intervals based on total mass and total work as 
described in paragraph (b)(1) of this section:
[GRAPHIC] [TIFF OMITTED] TR30AP10.047

Where:

i = test interval number.
N = number of test intervals.
WF = weighting factor for the test interval as defined in the standard-
          setting part.
m = mass of emissions over the test interval as determined in paragraph 
          (c) of this section.
W = total work from the engine over the test interval as determined in 
          paragraph (d) of this section.
t = duration of the test interval.

Example:

N = 2
WF1 = 0.85
WF2 = 0.15
m1 = 1.3753 g
m2 = 0.4135 g
t1 = 120 s
t2 = 200 s
W1 = 2.8375 kW [middot] hr
W2 = 0.0 kW [middot] hr
[GRAPHIC] [TIFF OMITTED] TR30AP10.048

eNOxcomposite = 0.5001 g/kW [middot] hr

    (ii) Use the following equation if you calculate brake-specific 
emissions over test intervals based on the ratio of mass rate to power 
as described in paragraph (b)(2) of this section:

[[Page 206]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.202

Where:

i = test interval number.
N = number of test intervals.
WF = weighting factor for the test interval as defined in the standard-
          setting part.
mi = mean steady-state mass rate of emissions over the test interval as 
          determined in paragraph (e) of this section.
P = mean steady-state power over the test interval as described in 
          paragraph (e) of this section.

    Example: 
N = 2
WF1 = 0.85
WF2 = 0.15
mi1 = 2.25842 g/hr
mi2 = 0.063443 g/hr
P1 = 4.5383 kW
P2 = 0.0 kW
[GRAPHIC] [TIFF OMITTED] TR25OC16.203

eNOxcomposite = 0.5001 g/kW[micro]hr

    (h) Rounding. Round the final brake-specific emission values to be 
compared to the applicable standard only after all calculations are 
complete (including any drift correction, applicable deterioration 
factors, adjustment factors, and allowances) and the result is in g/(kW 
[middot] hr) or units equivalent to the units of the standard, such as 
g/(hp [middot] hr). See the definition of ``Round'' in Sec. 1065.1001.

[73 FR 37328, June 30, 2008, as amended at 73 FR 59332, Oct. 8, 2008; 75 
FR 23048, Apr. 30, 2010; 76 FR 57457, Sept. 15, 2011;79 FR 23799, Apr. 
28, 2014; 80 FR 9118, Feb. 19, 2015; 81 FR 74180, Oct. 25, 2016]



Sec. 1065.655  Chemical balances of fuel, intake air, and exhaust.

    (a) General. Chemical balances of fuel, intake air, and exhaust may 
be used to calculate flows, the amount of water in their flows, and the 
wet concentration of constituents in their flows. With one flow rate of 
either fuel, intake air, or exhaust, you may use chemical balances to 
determine the flows of the other two. For example, you may use chemical 
balances along with either intake air or fuel flow to determine raw 
exhaust flow. Note that chemical balance calculations require measured 
values for the flow rate of diesel exhaust fluid, if applicable.
    (b) Procedures that require chemical balances. We require chemical 
balances when you determine the following:
    (1) A value proportional to total work, W, when you choose to 
determine brake-specific emissions as described in Sec. 1065.650(f).
    (2) Raw exhaust molar flow rate either from measured intake air 
molar flow rate or from fuel mass flow rate as described in paragraph 
(f) of this section.
    (3) Raw exhaust molar flow rate from measured intake air molar flow 
rate and dilute exhaust molar flow rate, as described in paragraph (g) 
of this section.
    (4) The amount of water in a raw or diluted exhaust flow, [chi] 
H2Oexh, when you do not measure the amount of water to

[[Page 207]]

correct for the amount of water removed by a sampling system. Correct 
for removed water according to Sec. 1065.659.
    (5) The calculated total dilution air flow when you do not measure 
dilution air flow to correct for background emissions as described in 
Sec. 1065.667(c) and (d).
    (c) Chemical balance procedure. The calculations for a chemical 
balance involve a system of equations that require iteration. We 
recommend using a computer to solve this system of equations. You must 
guess the initial values of up to three quantities: The amount of water 
in the measured flow, xH2Oexh, fraction of dilution air in 
diluted exhaust, xdil/exh, and the amount of products on a 
C1 basis per dry mole of dry measured flow, 
xCcombdry. You may use time-weighted mean values of 
combustion air humidity and dilution air humidity in the chemical 
balance; as long as your combustion air and dilution air humidities 
remain within tolerances of [0.0025 mol/mol of their respective mean 
values over the test interval. For each emission concentration, [chi] , 
and amount of water, xH2Oexh, you must determine their 
completely dry concentrations, xdry and 
xH2Oexhdry. You must also use your fuel mixture's atomic 
hydrogen-to-carbon ratio, a, oxygen-to-carbon ratio, b, sulfur-to-carbon 
ratio, g, and nitrogen-to-carbon ratio, d, you may optionally account 
for diesel exhaust fluid (or other fluids injected into the exhaust), if 
applicable. You may calculate a, b, g, and d; based on measured fuel and 
diesel exhaust fluid composition or you may use default values as 
described in paragraph (e) of this section. Use the following steps to 
complete a chemical balance:
    (1) Convert your measured concentrations such as, 
xCO2meas, xNOmeas, and xH2Oint, to dry 
concentrations by dividing them by one minus the amount of water present 
during their respective measurements; for example: 
xH2OxCO2meas, xH2OxNOmeas, and xH2Oint. 
If the amount of water present during a ``wet'' measurement is the same 
as the unknown amount of water in the exhaust flow, xH2Oexh, 
iteratively solve for that value in the system of equations. If you 
measure only total NOX and not NO and NO2 
separately, use good engineering judgment to estimate a split in your 
total NOX concentration between NO and NO2 for the 
chemical balances. For example, if you measure emissions from a 
stoichiometric spark-ignition engine, you may assume all NOX 
is NO. For a compression-ignition engine, you may assume that your molar 
concentration of NOX, xNOx, is 75% NO and 25% 
NO2. For NO2 storage aftertreatment systems, you 
may assume xNOx is 25% NO and 75% NO2. Note that 
for calculating the mass of NOX emissions, you must use the 
molar mass of NO2 for the effective molar mass of all 
NOX species, regardless of the actual NO2 fraction 
of NOX.
    (2) Enter the equations in paragraph (c)(4) of this section into a 
computer program to iteratively solve for xH2Oexh, 
xCcombdry, and xdil/exh. Use good engineering 
judgment to guess initial values for xH2Oexh, 
xCcombdry, and xdil/exh. We recommend guessing an 
initial amount of water that is about twice the amount of water in your 
intake or dilution air. We recommend guessing an initial value of 
xCcombdry as the sum of your measured CO2, CO, and 
THC values. We also recommend guessing an initial xdil/exh 
between 0.75 and 0.95, such as 0.8. Iterate values in the system of 
equations until the most recently updated guesses are all within [1% of 
their respective most recently calculated values.
    (3) Use the following symbols and subscripts in the equations for 
performing the chemical balance calculations in this paragraph (c):

xdil/exh = amount of dilution gas or excess air per mole of 
          exhaust.
xH2Oexh = amount of H2O in exhaust per mole of 
          exhaust.
xCcombdry = amount of carbon from fuel in the exhaust per 
          mole of dry exhaust.
xH2dry = amount of H2 in exhaust per amount of dry 
          exhaust.
KH2Ogas = water-gas reaction equilibrium coefficient. You may 
          use 3.5 or calculate your own value using good engineering 
          judgment.
xH2Oexhdry = amount of H2O in exhaust per dry mole 
          of dry exhaust.
xprod/intdry = amount of dry stoichiometric products per dry 
          mole of intake air.
xdil/exhdry = amount of dilution gas and/or excess air per 
          mole of dry exhaust.

[[Page 208]]

xint/exhdry = amount of intake air required to produce actual 
          combustion products per mole of dry (raw or diluted) exhaust.
xraw/exhdry = amount of undiluted exhaust, without excess 
          air, per mole of dry (raw or diluted) exhaust.
xO2int = amount of intake air O2 per mole of 
          intake air.
xCO2intdry = amount of intake air CO2 per mole of 
          dry intake air. You may use [chi] CO2intdry = 375 
          [micro] mol/mol, but we recommend measuring the actual 
          concentration in the intake air.
xH2Ointdry = amount of intake air H2O per mole of 
          dry intake air.
xCO2int = amount of intake air CO2 per mole of 
          intake air.
xCO2dil = amount of dilution gas CO2 per mole of 
          dilution gas.
xCO2dildry = amount of dilution gas CO2 per mole 
          of dry dilution gas. If you use air as diluent, you may use 
          [chi] CO2dildry = 375 [micro] mol/mol, but we 
          recommend measuring the actual concentration in the intake 
          air.
xH2Odildry = amount of dilution gas H2O per mole 
          of dry dilution gas.
xH2Odil = amount of dilution gas H2O per mole of 
          dilution gas.
x[emission]meas = amount of measured emission in the sample 
          at the respective gas analyzer.
x[emission]dry = amount of emission per dry mole of dry 
          sample.
xH2O[emission]meas = amount of H2O in sample at 
          emission-detection location. Measure or estimate these values 
          according to Sec. 1065.145(e)(2).
xH2Oint = amount of H2O in the intake air, based 
          on a humidity measurement of intake air.
a = atomic hydrogen-to-carbon ratio of the fuel (or mixture of test 
          fuels) and any injected fluids.
b = atomic oxygen-to-carbon ratio of the fuel (or mixture of test fuels) 
          and any injected fluids.
g = atomic sulfur-to-carbon ratio of the fuel (or mixture of test fuels) 
          and any injected fluids.
d = atomic nitrogen-to-carbon ratio of the fuel (or mixture of test 
          fuels) and any injected fluids.

    (4) Use the following equations to iteratively solve for 
xdil/exh, xH2Oexh, and xCcombdry:
[GRAPHIC] [TIFF OMITTED] TR30AP10.051

[GRAPHIC] [TIFF OMITTED] TR30AP10.052

[GRAPHIC] [TIFF OMITTED] TR30AP10.053

[GRAPHIC] [TIFF OMITTED] TR30AP10.054

[GRAPHIC] [TIFF OMITTED] TR30AP10.055

[GRAPHIC] [TIFF OMITTED] TR30AP10.056

[GRAPHIC] [TIFF OMITTED] TR30AP10.057

[GRAPHIC] [TIFF OMITTED] TR30AP10.058

[GRAPHIC] [TIFF OMITTED] TR30AP10.059


[[Page 209]]


[GRAPHIC] [TIFF OMITTED] TR30AP10.060

[GRAPHIC] [TIFF OMITTED] TR30AP10.061

[GRAPHIC] [TIFF OMITTED] TR30AP10.062

[GRAPHIC] [TIFF OMITTED] TR30AP10.063

[GRAPHIC] [TIFF OMITTED] TR30AP10.064

[GRAPHIC] [TIFF OMITTED] TR30AP10.065

[GRAPHIC] [TIFF OMITTED] TR30AP10.066

[GRAPHIC] [TIFF OMITTED] TR30AP10.067

[GRAPHIC] [TIFF OMITTED] TR30AP10.068

    (5) The following example is a solution for xdil/exh,x, 
xH2Oexh, and xCcombdry using the equations in 
paragraph (c)(4) of this section:
[GRAPHIC] [TIFF OMITTED] TR15SE11.050


[[Page 210]]


[GRAPHIC] [TIFF OMITTED] TR15SE11.051


[[Page 211]]


[GRAPHIC] [TIFF OMITTED] TR15SE11.052

a = 1.8
b = 0.05
g = 0.0003
d = 0.0001

    (d) Carbon mass fraction of fuel. Determine carbon mass fraction of 
fuel, wC, based on the fuel properties as determined in 
paragraph (e) of this section,

[[Page 212]]

accounting for diesel exhaust fluid's contribution to a, b, g, and d, or 
that of any other fluid injected into the exhaust, if applicable. 
Calculate wC using the following equation:
[GRAPHIC] [TIFF OMITTED] TR25OC16.204

Where:

wC = carbon mass fraction of the fuel (or mixture of test 
          fuels) and any injected fluids.
MC = molar mass of carbon.
a = atomic hydrogen-to-carbon ratio of the fuel (or mixture of test 
          fuels) and any injected fluids.
MH = molar mass of hydrogen.
b = atomic oxygen-to-carbon ratio of the fuel (or mixture of test fuels) 
          and any injected fluids.
MO = molar mass of oxygen.
g = atomic sulfur-to-carbon ratio of the fuel (or mixture of test fuels) 
          and any injected fluids.
MS = molar mass of sulfur.
d = atomic nitrogen-to-carbon ratio of the fuel (or mixture of test 
          fuels) and any injected fluids.
MN = molar mass of nitrogen.

    Example: 
a = 1.8
b = 0.05
g = 0.0003
d = 0.0001
MC = 12.0107
MH = 1.00794
MO = 15.9994
MS = 32.065
MN = 14.0067
[GRAPHIC] [TIFF OMITTED] TR25OC16.205

wC = 0.8206

    (e) Fuel and diesel exhaust fluid composition. Determine fuel and 
diesel exhaust fluid composition represented by a, b, g, and d as 
described in this paragraph (e). When using measured fuel or diesel 
exhaust fluid properties, you must determine values for a and b; in all 
cases. If you determine compositions based on measured values and the 
default value listed in Table 1 of this section is zero, you may set g 
and d to zero; otherwise determine g and d (along with a and b) based on 
measured values. Determine elemental mass fractions and values for a, b, 
g, and d as follows:
    (1) For liquid fuels, use the default values for a, b, g, and d in 
Table 1 of this section or determine mass fractions of liquid fuels for 
calculation of a, b, g, and d as follows:
    (i) Determine the carbon and hydrogen mass fractions according to 
ASTM D5291 (incorporated by reference in Sec. 1065.1010). When using 
ASTM D5291 to determine carbon and hydrogen mass fractions of gasoline 
(with or without blended ethanol), use good engineering judgment to 
adapt the method as appropriate. This may include consulting with the 
instrument manufacturer on how to test high-volatility fuels. Allow the 
weight of volatile fuel samples to stabilize for 20 minutes before 
starting the analysis; if the weight still drifts after 20 minutes, 
prepare a new sample. Retest the sample if the carbon, hydrogen, and 
oxygen mass fractions do not add up to a total mass of 100 [0.5%; if you 
do not measure oxygen, you may assume it has a zero concentration for 
this specification.
    (ii) Determine oxygen mass fraction of gasoline (with or without 
blended ethanol) according to ASTM D5599 (incorporated by reference in 
Sec. 1065.1010). For all other liquid fuels, determine

[[Page 213]]

the oxygen mass fraction using good engineering judgment.
    (iii) Determine the nitrogen mass fraction according to ASTM D4629 
or ASTM D5762 (incorporated by reference in Sec. 1065.1010) for all 
liquid fuels. Select the correct method based on the expected nitrogen 
content.
    (iv) Determine the sulfur mass fraction according to subpart H of 
this part.
    (2) For gaseous fuels and diesel exhaust fluid, use the default 
values for a, b, g, and d in Table 1 of this section, or use good 
engineering judgment to determine those values based on measurement.
    (3) For nonconstant fuel mixtures, you must account for the varying 
proportions of the different fuels. This generally applies for dual-fuel 
engines, but it also applies if diesel exhaust fluid is injected in a 
way that is not strictly proportional to fuel flow. Account for these 
varying concentrations either with a batch measurement that provides 
averaged values to represent the test interval, or by analyzing data 
from continuous mass rate measurements. Application of average values 
from a batch measurement generally applies to situations where one fluid 
is a minor component of the total fuel mixture, for example dual-fuel 
engines with diesel pilot injection, where the diesel pilot fuel mass is 
less than 5% of the total fuel mass and diesel exhaust fluid injection; 
consistent with good engineering judgment.
    (4) Calculate a, b, g, and d using the following equations:
    [GRAPHIC] [TIFF OMITTED] TR25OC16.206
    
    [GRAPHIC] [TIFF OMITTED] TR25OC16.207
    
    [GRAPHIC] [TIFF OMITTED] TR25OC16.208
    

[[Page 214]]


[GRAPHIC] [TIFF OMITTED] TR25OC16.209

Where:

M = total number of fuels and injected fluids over the duty cycle.
j = an indexing variable that represents one fuel or injected fluid, 
          starting with j = 1.
mj = the mass flow rate of the fuel or any injected fluid j. 
          For applications using a single fuel and no DEF fluid, set 
          this value to 1. For batch measurements, divide the total mass 
          of fuel over the test interval duration to determine a mass 
          rate.
WHj = hydrogen mass fraction of fuel or any injected fluid j.
WCj = carbon mass fraction of fuel or any injected fluid j.
WOj = oxygen mass fraction of fuel or any injected fluid j.
WSj = sulfur mass fraction of fuel or any injected fluid j.
WNj = nitrogen mass fraction of fuel or any injected fluid j.

    Example: 
N = 1
j = 1
mj = 1
WHj = 0.1239
WCj = 0.8206
WOj = 0.0547
WSj = 0.00066
WNj = 0.000095
MC = 12.0107
MH = 1.00794
MO = 15.9994
MS = 32.065
MN = 14.0067
[GRAPHIC] [TIFF OMITTED] TR25OC16.210

[GRAPHIC] [TIFF OMITTED] TR25OC16.317

a = 1.799
b = 0.05004
g = 0.0003012
d = 0.0001003

    Table 1 of Sec. 1065.655--Default Values of a, b, g, d, and WC
------------------------------------------------------------------------
                                      Atomic hydrogen,
                                     oxygen, sulfur, and    Carbon mass
      Fuel or injected fluid         nitrogen-to-carbon   fraction, WC g/
                                       ratios CHaObSg            g
                                          N[delta]
------------------------------------------------------------------------
Gasoline..........................  CH1.85O0S0N0........           0.866
E10 Gasoline......................  CH1.92O0.03S0N0.....           0.833

[[Page 215]]

 
E15 Gasoline......................  CH1.95O0.05S0N0.....           0.817
E85 Gasoline......................  CH2.73O0.38S0N0.....           0.576
E100 Ethanol......................  CH3O0.5S0N0.........           0.521
M100 Methanol.....................  CH4O1S0N0...........           0.375
1 Diesel.........................  CH1.93O0S0N0........           0.861
2 Diesel.........................  CH1.80O0S0N0........           0.869
Liquefied petroleum gas...........  CH2.64O0S0N0........           0.819
Natural gas.......................  CH3.78 O0.016S0N0...           0.747
Residual fuel blends..............   Must be determined by measured fuel
                                          properties as described in
                                      paragraph (d)(1) of this section.
                                   -------------------------------------
Diesel exhaust fluid..............  CH17.85O7.92S0N2....           0.065
------------------------------------------------------------------------

    (f) Calculated raw exhaust molar flow rate from measured intake air 
molar flow rate or fuel mass flow rate. You may calculate the raw 
exhaust molar flow rate from which you sampled emissions, 
nexh, based on the measured intake air molar flow rate, 
nint, or the measured fuel mass flow rate, mfuel, 
and the values calculated using the chemical balance in paragraph (c) of 
this section. The chemical balance must be based on raw exhaust gas 
concentrations. Solve for the chemical balance in paragraph (c) of this 
section at the same frequency that you update and record or 
nint or mfuel. For laboratory tests, calculating 
raw exhaust molar flow rate using measured fuel mass flow rate is valid 
only for steady-state testing. See Sec. 1065.915(d)(5)(iv) for 
application to field testing.
    (1) Crankcase flow rate. If engines are not subject to crankcase 
controls under the standard-setting part, you may calculate raw exhaust 
flow based on nint or mfuel using one of the 
following:
    (i) You may measure flow rate through the crankcase vent and 
subtract it from the calculated exhaust flow.
    (ii) You may estimate flow rate through the crankcase vent by 
engineering analysis as long as the uncertainty in your calculation does 
not adversely affect your ability to show that your engines comply with 
applicable emission standards.
    (iii) You may assume your crankcase vent flow rate is zero.
    (2) Intake air molar flow rate calculation. Calculate 
nexh based on nint using the following equation:
[GRAPHIC] [TIFF OMITTED] TR28AP14.049

Where:

nexh = raw exhaust molar flow rate from which you measured 
          emissions.
nint = intake air molar flow rate including humidity in 
          intake air.

Example:

nint = 3.780 mol/s
xint/exhdry = 0.69021 mol/mol
xraw/exhdry = 1.10764 mol/mol
xH20exhdry = 107.64 mmol/mol = 0.10764 mol/mol

[[Page 216]]

[GRAPHIC] [TIFF OMITTED] TR28AP14A.050

    (3) Fluid mass flow rate calculation. This calculation may be used 
only for steady-state laboratory testing. See Sec. 1065.915(d)(5)(iv) 
for application to field testing. Calculate nexh based on 
using the following equation:
[GRAPHIC] [TIFF OMITTED] TR25OC16.211

Where:

nexh = raw exhaust molar flow rate from which you measured 
          emissions.
N = total number of fuels and injected fluids over the duty cycle.
j = an indexing variable that represents one fuel or injected fluid, 
          starting with j = 1.
mj = the mass flow rate of the fuel or any injected fluid j.

    Example: 
N = 1
j = 1
mj = 7.559 g/s
wC = 0.869 g/g
MC = 12.0107 g/mol
xCcombdry = 99.87 mmol/mol = 0.09987 mol/mol
xH20exhdry = 107.64 mmol/mol = 0.10764 mol/mol
[GRAPHIC] [TIFF OMITTED] TR25OC16.212

nexh = 6.066 mol/s

    (g) Calculated raw exhaust molar flow rate from measured intake air 
molar flow rate, dilute exhaust molar flow rate, and dilute chemical 
balance. You may calculate the raw exhaust molar flow rate, 
nexh, based on the measured intake air molar flow rate, 
nint, the measured dilute exhaust molar flow rate, 
ndexh, and the values calculated using the chemical balance 
in paragraph (c) of this section. Note that the chemical balance must be 
based on dilute exhaust gas concentrations. For continuous-flow 
calculations, solve for the chemical balance in paragraph (c) of this 
section at the same frequency that you update and record nint 
and ndexh. This calculated nexh may be used for 
the PM dilution ratio verification in Sec. 1065.546; the calculation of 
dilution air molar flow rate in the background correction in Sec. 
1065.667; and the calculation of mass of emissions in Sec. 1065.650(c) 
for species that are measured in the raw exhaust.
    (1) Crankcase flow rate. If engines are not subject to crankcase 
controls under the standard-setting part, calculate raw exhaust flow as 
described in paragraph (e)(1) of this section.
    (2) Dilute exhaust and intake air molar flow rate calculation. 
Calculate nexh as follows:

[[Page 217]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.052

Example:

nint = 7.930 mol/s
xraw/exhdry = 0.1544 mol/mol
xint/exhdry = 0.1451 mol/mol
xH20/exh = 32.46 mmol/mol = 0.03246 mol/mol
ndexh = 49.02 mol/s
nexh = (0.1544 - 0.1451) [middot] (1 - 0.03246) [middot] 
          49.02 + 7.930 = 0.4411 + 7.930 = 8.371 mol/s

[73 FR 37331, June 30, 2008, as amended at 73 FR 59334, Oct. 8, 2008; 75 
FR 23051, Apr. 30, 2010; 76 FR 57458, Sept. 15, 2011; 79 FR 23799, Apr. 
28, 2014; 81 FR 74182, Oct. 25, 2016]



Sec. 1065.659  Removed water correction.

    (a) If you remove water upstream of a concentration measurement, x, 
correct for the removed water. Perform this correction based on the 
amount of water at the concentration measurement, 
xH2O[emission]meas, and at the flow meter, 
xH2Oexh, whose flow is used to determine the mass emission 
rate or total mass over a test interval. For continuous analyzers 
downstream of a sample dryer for transient and ramped-modal cycles, you 
must apply this correction on a continuous basis over the test interval, 
even if you use one of the options in Sec. 1065.145(e)(2) that results 
in a constant value for xH2O[emission]meas because 
xH2Oexh varies over the test interval. For batch analyzers, 
determine the flow-weighted average based on the continuous 
xH2Oexh values determined as described in paragraph (c) of 
this section. For batch analyzers, you may determine the flow-weighted 
average xH2Oexh based on a single value of xH2Oexh 
determined as described in paragraphs (c)(2) and (3) of this section, 
using flow-weighted average or batch concentration inputs.
    (b) Determine the amount of water remaining downstream of a sample 
dryer and at the concentration measurement using one of the methods 
described in Sec. 1065.145(e)(2). If you use a sample dryer upstream of 
an analyzer and if the calculated amount of water remaining downstream 
of the sample dryer and at the concentration measurement, 
xH2O[emission]meas, is higher than the amount of water at the 
flow meter, xH2Oexh, set xH2O[emission]meas equal 
to xH2Oexh. If you use a sample dryer upstream of storage 
media, you must be able to demonstrate that the sample dryer is removing 
water continuously (i.e., xH2Oexh is higher than 
xH2O[emission]meas throughout the test interval).
    (c) For a concentration measurement where you did not remove water, 
you may set xH2O[emission]meas equal to xH2Oexh. 
You may determine the amount of water at the flow meter, 
xH2Oexh, using any of the following methods:
    (1) Measure the dewpoint and absolute pressure and calculate the 
amount of water as described in Sec. 1065.645.
    (2) If the measurement comes from raw exhaust, you may determine the 
amount of water based on intake-air humidity, plus a chemical balance of 
fuel, intake air, and exhaust as described in Sec. 1065.655.
    (3) If the measurement comes from diluted exhaust, you may determine 
the amount of water based on intake-air humidity, dilution air humidity, 
and a chemical balance of fuel, intake air, and exhaust as described in 
Sec. 1065.655.
    (d) Perform a removed water correction to the concentration 
measurement using the following equation:

[[Page 218]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.053


[73 FR 37335, June 30, 2008, as amended at 76 FR 57462, Sept. 15, 2011; 
79 FR 23804, Apr. 28, 2014]



Sec. 1065.660  THC, NMHC, NMNEHC, CH4, 
and C2H6 determination.

    (a) THC determination and initial THC/CH4 contamination 
corrections. (1) If we require you to determine THC emissions, calculate 
xTHC[THC-FID]cor using the initial THC contamination 
concentration xTHC[THC-FID]init from Sec. 1065.520 as 
follows:
[GRAPHIC] [TIFF OMITTED] TR15SE11.058

Example:

xTHCuncor = 150.3 [micro] mol/mol
xTHCinit = 1.1 [micro] mol/mol
xTHCcor = 150.3--1.1
xTHCcor = 149.2 [micro] mol/mol

    (2) For the NMHC determination described in paragraph (b) of this 
section, correct xTHC[THC-FID] for initial THC contamination 
using Eq. 1065.660-1. You may correct xTHC[NMC-FID] for 
initial contamination of the CH4 sample train using Eq. 
1065.660-1, substituting in CH4 concentrations for THC.
    (3) For the NMNEHC determination described in paragraph (c) of this 
section, correct xTHC[THC-FID] for initial THC contamination 
using Eq. 1065.660-1. You may correct xTHC[NMC-FID] for 
initial contamination of the CH4 sample train using Eq. 
1065.660-1, substituting in CH4 concentrations for THC.
    (4) For the CH4 determination described in paragraph (d) 
of this section,

[[Page 219]]

you may correct xTHC[NMC-FID] for initial THC contamination 
of the CH4 sample train using Eq. 1065.660-1, substituting in 
CH4 concentrations for THC.
    (b) NMHC determination. Use one of the following to determine NMHC 
concentration, xNMHC:
    (1) If you do not measure CH4, you may omit the 
calculation of NMHC concentrations and calculate the mass of NMHC as 
described in Sec. 1065.650(c)(5).
    (2) For nonmethane cutters, calculate xNMHC using the 
nonmethane cutter's penetration fraction (PF) of CH4 and the 
response factor penetration fraction (RFPF) of 
C2H6 from Sec. 1065.365, the response factor (RF) 
of the THC FID to CH4 from Sec. 1065.360, the initial THC 
contamination and dry-to-wet corrected THC concentration 
xTHC[THC-FID]cor as determined in paragraph (a) of this 
section, and the dry-to-wet corrected CH4 concentration 
xTHC[NMC-FID]cor optionally corrected for initial THC 
contamination as determined in paragraph (a) of this section.
    (i) Use the following equation for penetration fractions determined 
using an NMC configuration as outlined in Sec. 1065.365(d):
[GRAPHIC] [TIFF OMITTED] TR15SE11.059

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID during sampling while bypassing the NMC.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
          contamination (optional) and dry-to-wet corrected, as measured 
          by the NMC FID during sampling through the NMC.
RFCH4[THC-FID] = response factor of THC FID to 
          CH4, according to Sec. 1065.360(d).
RFPFC2H6[NMC-FID] = nonmethane cutter combined ethane 
          response factor and penetration fraction, according to Sec. 
          1065.365(d).

Example:

xTHC[THC-FID]cor = 150.3 [micro] mol/mol
xTHC[NMC-FID]cor = 20.5 [micro] mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR15SE11.060

xNMHC = 131.4 [micro] mol/mol

    (ii) For penetration fractions determined using an NMC configuration 
as outlined in section Sec. 1065.365(e), use the following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.061

Where:

xNMHC = concentration of NMHC.

[[Page 220]]

xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID during sampling while bypassing the NMC.
PFCH4[NMC-FID] = nonmethane cutter CH4 penetration 
          fraction, according to Sec. 1065.365(e).
xTHC[NMC-FID]cor = concentration of THC, initial THC 
          contamination (optional) and dry-to-wet corrected, as measured 
          by the THC FID during sampling through the NMC.
PFC2H6[NMC-FID] = nonmethane cutter ethane penetration 
          fraction, according to Sec. 1065.365(e).

Example:

xTHC[THC-FID]cor = 150.3 [micro] mol/mol
PFCH4[NMC-FID] = 0.990
xTHC[NMC-FID]cor = 20.5 [micro] mol/mol
PFC2H6[NMC-FID] = 0.020
[GRAPHIC] [TIFF OMITTED] TR15SE11.062

xNMHC = 132.3 [micro] mol/mol

    (iii) For penetration fractions determined using an NMC 
configuration as outlined in section Sec. 1065.365(f), use the 
following equation:
[GRAPHIC] [TIFF OMITTED] TR15SE11.063

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID during sampling while bypassing the NMC.
PFCH4[NMC-FID] = nonmethane cutter CH4 penetration 
          fraction, according to Sec. 1065.365(f).
xTHC[NMC-FID]cor = concentration of THC, initial THC 
          contamination (optional) and dry-to-wet corrected, as measured 
          by the THC FID during sampling through the NMC.
RFPFC2H6[NMC-FID] = nonmethane cutter CH4 combined 
          ethane response factor and penetration fraction, according to 
          Sec. 1065.365(f).
RFCH4[THC-FID] = response factor of THC FID to 
          CH4, according to Sec. 1065.360(d).

Example:

xTHC[THC-FID]cor = 150.3 [micro] mol/mol
PFCH4[NMC-FID] = 0.990
xTHC[NMC-FID]cor = 20.5 [micro] mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 0.980
[GRAPHIC] [TIFF OMITTED] TR15SE11.067

xNMHC = 132.5 [micro] mol/mol

    (3) For a GC-FID or FTIR, calculate xNMHC using the THC 
analyzer's response factor (RF) for CH4, from Sec. 1065.360, 
and the initial THC contamination and dry-to-wet corrected THC 
concentration xTHC[THC-FID]cor as determined in paragraph (a) 
of this section as follows:

[[Page 221]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.213

Where:

xNMHC = concentration of NMHC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID.
RFCH4[THC-FID] = response factor of THC-FID to 
          CH4.
xCH4 = concentration of CH4, dry-to-wet corrected, 
          as measured by the GC-FID or FTIR.

    Example: 
xTHC[THC-FID]cor = 145.6 [micro] mol/mol
RFCH4[THC-FID] = 0.970
xCH4 = 18.9 [micro] mol/mol
xNMHC = 145.6-0.970 [middot] 18.9
xNMHC = 127.3 [micro] mol/mol
    (4) For an FTIR, calculate xNMHC by summing the 
hydrocarbon species listed in Sec. 1065.266(c) as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.214

Where:

xNMHC = concentration of NMHC.
xHCi = the C1-equivalent concentration of 
          hydrocarbon species i as measured by the FTIR, not corrected 
          for initial contamination.
xHCi-init = the C1-equivalent concentration of the 
          initial system contamination (optional) of hydrocarbon species 
          i, dry-to-wet corrected, as measured by the FTIR.
    Example: 
xC2H6 = 4.9 [micro] mol/mol
xC2H4 = 0.9 [micro] mol/mol
xC2H2 = 0.8 [micro] mol/mol
xC3H8 = 0.4 [micro] mol/mol
xC3H6 = 0.5 [micro] mol/mol
xC4H10 = 0.3 [micro] mol/mol
xCH2O = 0.8 [micro] mol/mol
xC2H4O = 0.3 [micro] mol/mol
xC2H2O2 = 0.1 [micro] mol/mol
xCH4O = 0.1 [micro] mol/mol
xNMHC = 4.9 + 0.9 + 0.8 + 0.4 + 0.5 + 0.3 + 0.8 + 0.3 + 0.1 + 
          0.1
xNMHC = 9.1 [micro] mol/mol

    (c) NMNEHC determination. Use one of the following methods to 
determine NMNEHC concentration, xNMNEHC:
    (1) If the content of your test fuel contains less than 0.010 mol/
mol of ethane, you may omit the calculation of NMNEHC concentrations and 
calculate the mass of NMNEHC as described in Sec. 1065.650(c)(6).
    (2) For a GC-FID or FTIR, calculate xNMNEHC using the THC 
analyzer's response factors (RF) for CH4 and 
C2H6, from Sec. 1065.360, and the initial 
contamination and dry-to-wet corrected THC concentration 
xTHC[THC-FID]cor as determined in paragraph (a) of this 
section as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.215

Where:

xNMNEHC = concentration of NMNEHC.

[[Page 222]]

xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID.
RFCH4[THC-FID] = response factor of THC-FID to 
          CH4.
xCH4 = concentration of CH4, dry-to-wet corrected, 
          as measured by the GC-FID or FTIR.
RFC2H6[THC-FID] = response factor of THC-FID to 
          C2H6.
xC2H6 = the C1-equivalent concentration of 
          C2H6, dry-to-wet corrected, as measured 
          by the GC-FID or FTIR.
    Example: 
xTHC[THC-FID]cor = 145.6 [micro] mol/mol
RFCH4[THC-FID] = 0.970
xCH4 = 18.9 [micro] mol/mol
RFC2H6[THC-FID] = 1.02
xC2H6 = 10.6 [micro] mol/mol
xNMHC = 145.6--0.970 [middot] 18.9--1.02 [middot] 10.6
xNMHC = 116.5 [micro] mol/mol

    (3) For an FTIR, calculate xNMNEHC by summing the 
hydrocarbon species listed in Sec. 1065.266(c) as follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.216

Where:

xNMNEHC = concentration of NMNEHC.
xHCi = the C1-equivalent concentration of 
          hydrocarbon species i as measured by the FTIR, not corrected 
          for initial contamination.
xHCi-init = the C1-equivalent concentration of the 
          initial system contamination (optional) of hydrocarbon species 
          i, dry-to-wet corrected, as measured by the FTIR.
    Example: 
xC2H4 = 0.9 [micro] mol/mol
xC2H2 = 0.8 [micro] mol/mol
xC3H8 = 0.4 [micro] mol/mol
xC3H6 = 0.5 [micro] mol/mol
xC4H10 = 0.3 [micro] mol/mol
xCH2O = 0.8 [micro] mol/mol
xC2H4O = 0.3 [micro] mol/mol
xC2H2O2 = 0.1 [micro] mol/mol
xCH4O = 0.1 [micro] mol/mol
xNMNEHC = 0.9 + 0.8 + 0.4 + 0.5 + 0.3 + 0.8 + 0.3 + 0.1 + 0.1
xNMNEHC = 4.2 [micro] mol/mol

    (d) CH4 determination. Use one of the following methods 
to determine CH4 concentration, xCH4:
    (1) For nonmethane cutters, calculate xCH4 using the 
nonmethane cutter's penetration fraction (PF) of CH4 and the 
response factor penetration fraction (RFPF) of 
C2H6 from Sec. 1065.365, the response factor (RF) 
of the THC FID to CH4 from Sec. 1065.360, the initial THC 
contamination and dry-to-wet corrected THC concentration 
xTHC[THC-FID]cor as determined in paragraph (a) of this 
section, and the dry-to-wet corrected CH4 concentration 
xTHC[NMC-FID]cor optionally corrected for initial THC 
contamination as determined in paragraph (a) of this section.
    (i) Use the following equation for penetration fractions determined 
using an NMC configuration as outlined in Sec. 1065.365(d):
[GRAPHIC] [TIFF OMITTED] TR25OC16.217

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
          contamination (optional) and dry-

[[Page 223]]

          to-wet corrected, as measured by the NMC FID during sampling 
          through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID during sampling while bypassing the NMC.
RFPFC2H6[NMC-FID] = the combined ethane response factor and 
          penetration fraction of the nonmethane cutter, according to 
          Sec. 1065.365(d).
RFCH4[THC-FID] = response factor of THC FID to 
          CH4, according to Sec. 1065.360(d).

    Example: 
xTHC[NMC-FID]cor = 10.4 [micro] mol/mol
xTHC[THC-FID]cor = 150.3 [micro] mol/mol
RFPFC2H6[NMC-FID] = 0.019
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR25OC16.218

xCH4 = 7.69 [micro] mol/mol

    (ii) For penetration fractions determined using an NMC configuration 
as outlined in Sec. 1065.365(e), use the following equation:
[GRAPHIC] [TIFF OMITTED] TR25OC16.219

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
          contamination (optional) and dry-to-wet corrected, as measured 
          by the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID during sampling while bypassing the NMC.
PFC2H6[NMC-FID] = nonmethane cutter ethane penetration 
          fraction, according to Sec. 1065.365(e).
RFCH4[THC-FID] = response factor of THC FID to 
          CH4, according to Sec. 1065.360(d).
PFCH4[NMC-FID] = nonmethane cutter CH4 penetration 
          fraction, according to Sec. 1065.365(e).

    Example: 
xTHC[NMC-FID]cor = 10.4 [micro] mol/mol
xTHC[THC-FID]cor = 150.3 [micro] mol/mol
PFC2H6[NMC-FID] = 0.020
RFCH4[THC-FID] = 1.05
PFCH4[NMC-FID] = 0.990
[GRAPHIC] [TIFF OMITTED] TR25OC16.220

xCH4 = 7.25 [micro] mol/mol

    (iii) For penetration fractions determined using an NMC 
configuration as outlined in Sec. 1065.365(f), use the following 
equation:

[[Page 224]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.221

Where:

xCH4 = concentration of CH4.
xTHC[NMC-FID]cor = concentration of THC, initial THC 
          contamination (optional) and dry-to-wet corrected, as measured 
          by the NMC FID during sampling through the NMC.
xTHC[THC-FID]cor = concentration of THC, initial THC 
          contamination and dry-to-wet corrected, as measured by the THC 
          FID during sampling while bypassing the NMC.
RFPFC2H6[NMC-FID] = the combined ethane response factor and 
          penetration fraction of the nonmethane cutter, according to 
          Sec. 1065.365(f).
PFCH4[NMC-FID] = nonmethane cutter CH4 penetration 
          fraction, according to Sec. 1065.365(f).
RFCH4[THC-FID] = response factor of THC FID to 
          CH4, according to Sec. 1065.360(d).

    Example: 
xTHC[NMC-FID]cor = 10.4 [micro] mol/mol
xTHC[THC-FID]cor = 150.3 [micro] mol/mol
RFPFC2H6[NMC-FID] = 0.019
PFCH4[NMC-FID] = 0.990
RFCH4[THC-FID] = 1.05
[GRAPHIC] [TIFF OMITTED] TR25OC16.222

xCH4 = 7.78 [micro] mol/mol

    (2) For a GC-FID or FTIR, xCH4 is the actual dry-to-wet 
corrected CH4 concentration as measured by the analyzer.
    (e) C2H6 determination. For a GC-FID or FTIR, xC2H6 is 
the C1-equivalent, dry-to-wet corrected 
C2H6 concentration as measured by the analyzer.

[76 FR 57462, Sept. 15, 2011, as amended at 81 FR 74184, Oct. 25, 2016]



Sec. 1065.665  THCE and NMHCE determination.

    (a) If you measured an oxygenated hydrocarbon's mass concentration, 
first calculate its molar concentration in the exhaust sample stream 
from which the sample was taken (raw or diluted exhaust), and convert 
this into a C1-equivalent molar concentration. Add these 
C1-equivalent molar concentrations to the molar concentration 
of non-oxygenated total hydrocarbon (NOTHC). The result is the molar 
concentration of total hydrocarbon equivalent (THCE). Calculate THCE 
concentration using the following equations, noting that Eq. 1065.665-3 
is required only if you need to convert your oxygenated hydrocarbon 
(OHC) concentration from mass to moles:
[GRAPHIC] [TIFF OMITTED] TR25OC16.223


[[Page 225]]


[GRAPHIC] [TIFF OMITTED] TR25OC16.224

[GRAPHIC] [TIFF OMITTED] TR25OC16.225

Where:

xTHCE = the sum of the C1-equivalent 
          concentrations of non-oxygenated hydrocarbon, alcohols, and 
          aldehydes.
xNOTHC = the sum of the C1-equivalent 
          concentrations of NOTHC.
xOHCi = the C1-equivalent concentration of 
          oxygenated species i in diluted exhaust, not corrected for 
          initial contamination.
xOHCi-init = the C1-equivalent concentration of 
          the initial system contamination (optional) of oxygenated 
          species i, dry-to-wet corrected.
xTHC[THC-FID]cor = the C1-equivalent response to 
          NOTHC and all OHC in diluted exhaust, HC contamination and 
          dry-to-wet corrected, as measured by the THC-FID.
RFOHCi[THC-FID] = the response factor of the FID to species i 
          relative to propane on a C1-equivalent basis.
C# = the mean number of carbon atoms in the particular 
          compound.
Mdexh = the molar mass of diluted exhaust as determine in 
          Sec. 1065.340.
mdexhOHCi = the mass of oxygenated species i in dilute 
          exhaust.
MOHCi = the C1-equivalent molecular weight of 
          oxygenated species i.
mdexh = the mass of diluted exhaust
ndexhOHCi = the number of moles of oxygenated species i in 
          total diluted exhaust flow.
ndexh = the total diluted exhaust flow.

    (b) If we require you to determine nonmethane hydrocarbon equivalent 
(NMHCE), use the following equation:
[GRAPHIC] [TIFF OMITTED] TR25OC16.226

Where:

xNMHCE = the sum of the C1-equivalent 
          concentrations of nonoxygenated nonmethane hydrocarbon 
          (NONMHC), alcohols, and aldehydes.
RFCH4[THC-FID] = the response factor of THC-FID to 
          CH4.
xCH4 = concentration of CH4, HC contamination 
          (optional) and dry-to-wet corrected, as measured by the gas 
          chromatograph FID.

    (c) The following example shows how to determine NMHCE emissions 
based on ethanol (C2H5OH), methanol 
(CH3OH), acetaldehyde (C2H4O), and 
formaldehyde (CH2O) as C1-equivalent molar 
concentrations:

xTHC[THC-FID]cor = 145.6 [micro] mol/mol
xCH4 = 18.9 [micro] mol/mol
xC2H5OH = 100.8 [micro] mol/mol
xCH3OH = 1.1 [micro] mol/mol
xC2H4O = 19.1 [micro] mol/mol
xCH2O = 1.3 [micro] mol/mol
RFCH4[THC-FID] = 1.07
RFC2H5OH[THC-FID] = 0.76
RFCH3OH[THC-FID] = 0.74
RFH2H4O[THC-FID] = 0.50
RFCH2O[THC-FID] = 0.0

[[Page 226]]

xNMHCE = xTHC[THC-FID]cor - (xC2H5OH 
          [middot] RFC2H5OH[THC-FID] + xCH3OH 
          [middot] RFCH3OH[THC-FID] + xC2H4O 
          [middot] RFC2H4O[THC-FID] + xCH2O 
          [middot] RFCH2O[THC-FID]) + xC2H5OH + 
          xCH3OH + xC2H4O + xCH2O - 
          (RFCH4[THC-FID] [middot] xCH4)
xNMHCE = 145.6 - (100.8 [middot] 0.76 + 1.1 [middot] 0.74 + 
          19.1 [middot] 0.50 + 1.3 [middot] 0) + 100.8 + 1.1 + 19.1 + 
          1.3 - (1.07 [middot] 18.9)
xNMHCE = 160.71 [micro] mol/mol

[79 FR 23805, Apr. 28, 2014, as amended at 81 FR 74187, Oct. 25, 2016]



Sec. 1065.667  Dilution air background emission correction.

    (a) To determine the mass of background emissions to subtract from a 
diluted exhaust sample, first determine the total flow of dilution air, 
ndil, over the test interval. This may be a measured quantity 
or a calculated quantity. Multiply the total flow of dilution air by the 
mean mole fraction (i.e., concentration) of a background emission. This 
may be a time-weighted mean or a flow-weighted mean (e.g., a 
proportionally sampled background). Finally, multiply by the molar mass, 
M, of the associated gaseous emission constituent. The product of 
ndil and the mean molar concentration of a background 
emission and its molar mass, M, is the total background emission mass, 
m. In the case of PM, where the mean PM concentration is already in 
units of mass per mole of sample, MPM, multiply it by the 
total amount of dilution air flow, and the result is the total 
background mass of PM, mPM. Subtract total background mass 
from total mass to correct for background emissions.
    (b) You may determine the total flow of dilution air by a direct 
flow measurement.
    (c) You may determine the total flow of dilution air by subtracting 
the calculated raw exhaust molar flow as described in Sec. 1065.655(g) 
from the measured dilute exhaust flow. This may be done by totaling 
continuous calculations or by using batch results.
    (d) You may determine the total flow of dilution air from the 
measured dilute exhaust flow and a chemical balance of the fuel, intake 
air, and dilute exhaust as described in Sec. 1065.655. For this option, 
the molar flow of dilution air is calculated by multiplying the dilute 
exhaust flow by the mole fraction of dilution gas to dilute exhaust, 
xdil/exh, from the dilute chemical balance. This may be done 
by totaling continuous calculations or by using batch results. For 
example, to use batch results, the total flow of dilution air is 
calculated by multiplying the total flow of diluted exhaust, 
ndexh, by the flow-weighted mean mole fraction of dilution 
air in diluted exhaust, xdil/exh. Calculate 
xdil/exh using flow-weighted mean concentrations of emissions 
in the chemical balance, as described in Sec. 1065.655. The chemical 
balance in Sec. 1065.655 assumes that your engine operates 
stoichiometrically, even if it is a lean-burn engine, such as a 
compression-ignition engine. Note that for lean-burn engines this 
assumption could result in an error in emission calculations. This error 
could occur because the chemical balance in Sec. 1065.655 treats excess 
air passing through a lean-burn engine as if it was dilution air. If an 
emission concentration expected at the standard is about 100 times its 
dilution air background concentration, this error is negligible. 
However, if an emission concentration expected at the standard is 
similar to its background concentration, this error could be 
significant. If this error might affect your ability to show that your 
engines comply with applicable standards, we recommend that you either 
determine the total flow of dilution air using one of the more accurate 
methods in paragraph (b) or (c) of this section, or remove background 
emissions from dilution air by HEPA filtration, chemical adsorption, or 
catalytic scrubbing. You might also consider using a partial-flow 
dilution technique such as a bag mini-diluter, which uses purified air 
as the dilution air.
    (e) The following is an example of using the flow-weighted mean 
fraction of dilution air in diluted exhaust, xdil/exh, and 
the total mass of background emissions calculated using the total flow 
of diluted exhaust, ndexh, as described in Sec. 1065.650(c):

[[Page 227]]

[GRAPHIC] [TIFF OMITTED] TR15SE11.075

    Example:

MNOx = 46.0055 g/mol
xbkgnd = 0.05 [micro] mol/mol = 0.05[sdot]10-6 
          mol/mol
ndexh = 23280.5 mol
xdil/exh = 0.843 mol/mol
mbkgndNOxdexh = 
          46.0055[sdot]0.05[sdot]10-\6\[sdot]23280.5
mbkgndNOxdexh = 0.0536 g
mbkgndNOx = 0.843 [sdot] 0.0536
mbkgndNOx = 0.0452 g

    (f) The following is an example of using the fraction of dilution 
air in diluted exhaust, xdil/exh, and the mass rate of 
background emissions calculated using the flow rate of diluted exhaust, 
ndexh, as described in Sec. 1065.650(c):
[GRAPHIC] [TIFF OMITTED] TR15SE11.076

Example:

MNOx = 46.0055 g/mol
xbkgnd = 0.05 [micro] mol/mol = 0.05[sdot]10-\6\ 
          mol/mol
ndexh = 23280.5 mol/s
xdil/exh = 0.843 mol/mol
mbkgndNOxdexh = 
          46.0055[sdot]0.05[sdot]10-\6\[sdot]23280.5
mbkgndNOxdexh = 0.0536 g/hr
mbkgndNOx = 0.843 [sdot] 0.0536
mbkgndNOx = 0.0452 g/hr

[76 FR 57465, Sept. 15, 2011, as amended at 81 FR 74188, Oct. 25, 2016]



Sec. 1065.670  NOX intake-air humidity and temperature corrections.

    See the standard-setting part to determine if you may correct 
NOX emissions for the effects of intake-air humidity or 
temperature. Use the NOX intake-air humidity and temperature 
corrections specified in the standard-setting part instead of the 
NOX intake-air humidity correction specified in this part 
1065. If the standard-setting part does not prohibit correcting 
NOX emissions for intake-air humidity according to this part 
1065, correct NOX concentrations for intake-air humidity as 
described in this section. See Sec. 1065.650(c)(1) for the proper 
sequence for applying the NOX intake-air humidity and 
temperature corrections. You may use a time-weighted mean combustion air 
humidity to calculate this correction if your combustion air humidity 
remains within a tolerance of [0.0025 mol/mol of the mean value over the 
test interval. For intake-air humidity correction, use one of the 
following approaches:

[[Page 228]]

[GRAPHIC] [TIFF OMITTED] TR30AP10.095

Example:

xNOxuncor = 700.5 [micro] mol/mol
xH2O = 0.022 mol/mol
xNOxcor = 700.5 [middot] (9.953 [middot] 0.022 + 0.832)
xNOxcor = 736.2 [micro] mol/mol

    (b) For spark-ignition engines, correct for intake-air humidity 
using the following equation:
[GRAPHIC] [TIFF OMITTED] TR30AP10.096

Example:

xNOxuncor = 154.7 [micro] mol/mol
xH2O = 0.022 mol/mol
xNOxcor = 154.7 [middot] (18.840 [middot] 0.022 + 0.68094)
xNOxcor = 169.5 [micro] mol/mol

    (c) Develop your own correction, based on good engineering judgment.

[75 FR 23056, Apr. 30, 2010, as amended at 76 FR 57466, Sept. 15, 2011]



Sec. 1065.672  Drift correction.

    (a) Scope and frequency. Perform the calculations in this section to 
determine if gas analyzer drift invalidates the results of a test 
interval. If drift does not invalidate the results of a test interval, 
correct that test interval's gas analyzer responses for drift according 
to this section. Use the drift-corrected gas analyzer responses in all 
subsequent emission calculations. Note that the acceptable threshold for 
gas analyzer drift over a test interval is specified in Sec. 1065.550 
for both laboratory testing and field testing.
    (b) Correction principles. The calculations in this section utilize 
a gas analyzer's responses to reference zero and span concentrations of 
analytical gases, as determined sometime before and after a test 
interval. The calculations correct the gas analyzer's responses that 
were recorded during a test interval. The correction is based on an 
analyzer's mean responses to reference zero and span gases, and it is 
based on the reference concentrations of the zero and span gases 
themselves. Validate and correct for drift as follows:
    (c) Drift validation. After applying all the other corrections--
except drift correction--to all the gas analyzer signals, calculate 
brake-specific emissions according to Sec. 1065.650. Then correct all 
gas analyzer signals for drift according to this section. Recalculate 
brake-specific emissions using all of the drift-corrected gas analyzer 
signals. Validate and report the brake-specific emission results before 
and after drift correction according to Sec. 1065.550.
    (d) Drift correction. Correct all gas analyzer signals as follows:
    (1) Correct each recorded concentration, xi, for 
continuous sampling or for batch sampling, x.
    (2) Correct for drift using the following equation:
    [GRAPHIC] [TIFF OMITTED] TR24FE09.005
    
Where:

xidriftcorrected = concentration corrected for drift.
xrefzero = reference concentration of the zero gas, which is 
          usually zero unless known to be otherwise.

[[Page 229]]

xrefspan = reference concentration of the span gas.
xprespan = pre-test interval gas analyzer response to the 
          span gas concentration.
xpostspan = post-test interval gas analyzer response to the 
          span gas concentration.
xi or x = concentration recorded during test, before drift 
          correction.
xprezero = pre-test interval gas analyzer response to the 
          zero gas concentration.
xpostzero = post-test interval gas analyzer response to the 
          zero gas concentration.

Example:

xrefzero = 0 [micro] mol/mol
xrefspan = 1800.0 [micro] mol/mol
xprespan = 1800.5 [micro] mol/mol
xpostspan = 1695.8 [micro] mol/mol
xi or x = 435.5 [micro] mol/mol
xprezero = 0.6 [micro] mol/mol
xpostzero = -5.2 [micro] mol/mol
[GRAPHIC] [TIFF OMITTED] TR24FE09.006

xidriftcorrected = 450.2 [micro] mol/mol

    (3) For any pre-test interval concentrations, use concentrations 
determined most recently before the test interval. For some test 
intervals, the most recent pre-zero or pre-span might have occurred 
before one or more previous test intervals.
    (4) For any post-test interval concentrations, use concentrations 
determined most recently after the test interval. For some test 
intervals, the most recent post-zero or post-span might have occurred 
after one or more subsequent test intervals.
    (5) If you do not record any pre-test interval analyzer response to 
the span gas concentration, xprespan, set xprespan 
equal to the reference concentration of the span gas:

xprespan = xrefspan.

    (6) If you do not record any pre-test interval analyzer response to 
the zero gas concentration, xprezero, set xprezero 
equal to the reference concentration of the zero gas:

xprezero = xrefzero.

    (7) Usually the reference concentration of the zero gas, 
xrefzero, is zero: xrefzero = 0 [micro] mol/mol. 
However, in some cases you might know that xrefzero has a 
non-zero concentration. For example, if you zero a CO2 
analyzer using ambient air, you may use the default ambient air 
concentration of CO2, which is 375 [micro] mol/mol. In this 
case, xrefzero = 375 [micro] mol/mol. Note that when you zero 
an analyzer using a non-zero xrefzero, you must set the 
analyzer to output the actual xrefzero concentration. For 
example, if xrefzero = 375 [micro] mol/mol, set the analyzer 
to output a value of 375 [micro] mol/mol when the zero gas is flowing to 
the analyzer.

[70 FR 40516, July 13, 2005, as amended at 74 FR 8427, Feb. 24, 2009; 75 
FR 23056, Apr. 30, 2010]



Sec. 1065.675  CLD quench verification calculations.

    Perform CLD quench-check calculations as follows:
    (a) Perform a CLD analyzer quench verification test as described in 
Sec. 1065.370.
    (b) Estimate the maximum expected mole fraction of water during 
emission testing, xH2Oexp. Make this estimate where the 
humidified NO span gas was introduced in Sec. 1065.370(e)(6). When 
estimating the maximum expected mole fraction of water, consider the 
maximum expected water content in combustion air, fuel combustion 
products, and dilution air (if applicable). If you introduced the 
humidified NO span gas into the sample system upstream of a sample dryer 
during the verification test, you need not estimate the maximum expected 
mole fraction of water and you must set xH2Oexp equal to 
xH2Omeas.
    (c) Estimate the maximum expected CO2 concentration 
during emission testing, xCO2exp. Make this estimate at the 
sample system location where the blended NO and CO2 span 
gases are introduced according to Sec. 1065.370(d)(10). When estimating 
the maximum expected CO2 concentration, consider the maximum 
expected CO2 content in fuel combustion products and dilution 
air.

[[Page 230]]

    (d) Calculate quench as follows:
    [GRAPHIC] [TIFF OMITTED] TR25OC16.227
    
Where:

quench = amount of CLD quench.
xNOdry = concentration of NO upstream of a bubbler, according 
          to Sec. 1065.370(e)(4).
xNOwet = measured concentration of NO downstream of a 
          bubbler, according to Sec. 1065.370(e)(9).
xH2Oexp = maximum expected mole fraction of water during 
          emission testing, according to paragraph (b) of this section.
xH2Omeas = measured mole fraction of water during the quench 
          verification, according to Sec. 1065.370(e)(7).
xNOmeas = measured concentration of NO when NO span gas is 
          blended with CO2 span gas, according to Sec. 
          1065.370(d)(10).
xNOact = actual concentration of NO when NO span gas is 
          blended with CO2 span gas, according to Sec. 
          1065.370(d)(11) and calculated according to Eq. 1065.675-2.
xCO2exp = maximum expected concentration of CO2 
          during emission testing, according to paragraph (c) of this 
          section.
xCO2act = actual concentration of CO2 when NO span 
          gas is blended with CO2 span gas, according to 
          Sec. 1065.370(d)(9).
          [GRAPHIC] [TIFF OMITTED] TR25OC16.228
          
Where:

xNOspan = The NO span gas concentration input to the gas 
          divider, according to Sec. 1065.370(d)(5).
xCO2span = the CO2 span gas concentration input to 
          the gas divider, according to Sec. 1065.370(d)(4).

    Example: 
xNOdry = 1800.0 [micro] mol/mol
xNOwet = 1739.6 [micro] mol/mol
xH2Oexp = 0.030 mol/mol
xH2Omeas = 0.030 mol/mol
xNOmeas = 1515.2 [micro] mol/mol
xNOspan = 3001.6 [micro] mol/mol
xCO2exp = 3.2%
xCO2span = 6.1%
xCO2act = 2.98%

[[Page 231]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.229

quench = (-0.0036655-0.014020171)[micro]100% = -1.7685671%

[73 FR 59340, Oct. 8, 2008, as amended at 76 FR 57466, Sept. 15, 2011; 
81 FR 74188, Oct. 25, 2016]



Sec. 1065.680  Adjusting emission levels to account for infrequently
regenerating aftertreatment devices.

    This section describes how to calculate and apply emission 
adjustment factors for engines using aftertreatment technology with 
infrequent regeneration events that may occur during testing. These 
adjustment factors are typically calculated based on measurements 
conducted for the purposes of engine certification, and then used to 
adjust the results of testing related to demonstrating compliance with 
emission standards. For this section, ``regeneration'' means an intended 
event during which emission levels change while the system restores 
aftertreatment performance. For example, exhaust gas temperatures may 
increase temporarily to remove sulfur from adsorbers or to oxidize 
accumulated particulate matter in a trap. Also, ``infrequent'' refers to 
regeneration events that are expected to occur on average less than once 
over a transient or ramped-modal duty cycle, or on average less than 
once per mode in a discrete-mode test.
    (a) Apply adjustment factors based on whether there is active 
regeneration during a test segment. The test segment may be a test 
interval or a full duty cycle, as described in paragraph (b) of this 
section. For engines subject to standards over more than one duty cycle, 
you must develop adjustment factors under this section for each separate 
duty cycle. You must be able to identify active regeneration in a way 
that is readily apparent during all testing. All adjustment factors for 
regeneration are additive.
    (1) If active regeneration does not occur during a test segment, 
apply an upward adjustment factor, UAF, that will be added to the 
measured emission rate for that test segment. Use the following equation 
to calculate UAF:

[GRAPHIC] [TIFF OMITTED] TR25OC16.318

Where:

EFA[cycle] = the average emission factor over the test 
          segment as determined in paragraph (a)(4) of this section.
EFL[cycle] = measured emissions over a complete test segment 
          in which active regeneration does not occur.

    Example: 
EFARMC = 0.15 g/kW[micro]hr
EFLRMC = 0.11 g/kW[micro]hr
UAFRMC = 0.15 - 0.11 = 0.04 g/kW[micro]hr

    (2) If active regeneration occurs or starts to occur during a test 
segment, apply a downward adjustment factor, DAF, that will be 
subtracted from the

[[Page 232]]

measured emission rate for that test segment. Use the following equation 
to calculate DAF:
[GRAPHIC] [TIFF OMITTED] TR25OC16.230

Where:

EFH[cycle] = measured emissions over the test segment from a 
          complete regeneration event, or the average emission rate over 
          multiple complete test segments with regeneration if the 
          complete regeneration event lasts longer than one test 
          segment.

    Example: 
EFARMC = 0.15 g/kW[micro]hr
EFHRMC = 0.50 g/kW[micro]hr
DAFRMC = 0.50 - 0.15 = 0.35 g/kW[micro]hr

    (3) Note that emissions for a given pollutant may be lower during 
regeneration, in which case EFL would be greater than 
EFH, and both UAF and DAF would be negative.
    (4) Calculate the average emission factor, EFA, as 
follows:
[GRAPHIC] [TIFF OMITTED] TR25OC16.231

Where:

F[cycle] = the frequency of the regeneration event during the 
          test segment, expressed in terms of the fraction of equivalent 
          test segments during which active regeneration occurs, as 
          described in paragraph (a)(5) of this section.
    Example: 
FRMC = 0.10
EFARMC = 0.10 [middot] 0.50 + (1.00 - 0.10) [middot] 0.11 = 
          0.15 g/kW[micro]hr

    (5) The frequency of regeneration, F, generally characterizes how 
often a regeneration event occurs within a series of test segments. 
Determine F using the following equation, subject to the provisions of 
paragraph (a)(6) of this section:
[GRAPHIC] [TIFF OMITTED] TR25OC16.232

Where:

ir[cycle] = the number of successive test segments required 
          to complete an active regeneration, rounded up to the next 
          whole number.
if[cycle] = the number of test segments from the end of one 
          complete regeneration event to the start of the next active 
          regeneration, without rounding.

    Example: 
irRMC = 2
ifRMC = 17.86

[[Page 233]]

[GRAPHIC] [TIFF OMITTED] TR25OC16.233

    (6) Use good engineering judgment to determine ir and 
if, as follows:
    (i) For engines that are programmed to regenerate after a specific 
time interval, you may determine the duration of a regeneration event 
and the time between regeneration events based on the engine's design 
parameters. For other engines, determine these values based on 
measurements from in-use operation or from running repetitive duty 
cycles in a laboratory.
    (ii) For engines subject to standards over multiple duty cycles, 
such as for transient and steady-state testing, apply this same 
calculation to determine a value of F for each duty cycle.
    (iii) Consider an example for an engine that is designed to 
regenerate its PM filter 500 minutes after the end of the last 
regeneration event, with the regeneration event lasting 30 minutes. If 
the RMC takes 28 minutes, irRMC = 2 (30 / 28 = 1.07, which 
rounds up to 2), and ifRMC = 500 / 28 = 17.86.
    (b) Develop adjustment factors for different types of testing as 
follows:
    (1) Discrete-mode testing. Develop separate adjustment factors for 
each test mode (test interval) of a discrete-mode test. When measuring 
EFH, if a regeneration event has started but is not complete 
when you reach the end of the sampling time for a test interval, extend 
the sampling period for that test interval until the regeneration event 
is complete.
    (2) Ramped-modal and transient testing. Develop a separate set of 
adjustment factors for an entire ramped-modal cycle or transient duty 
cycle. When measuring EFH, if a regeneration event has 
started but is not complete when you reach the end of the duty cycle, 
start the next repeat test as soon as possible, allowing for the time 
needed to complete emission measurement and installation of new filters 
for PM measurement; in that case EFH is the average emission 
level for the test segments that included regeneration.
    (3) Accounting for cold-start measurements. For engines subject to 
cold-start testing requirements, incorporate cold-start operation into 
your analysis as follows:
    (i) Determine the frequency of regeneration, F, in a way that 
incorporates the impact of cold-start operation in proportion to the 
cold-start weighting factor specified in the standard-setting part. You 
may use good engineering judgment to determine the effect of cold-start 
operation analytically.
    (ii) Treat cold-start testing and hot-start testing together as a 
single test segment for adjusting measured emission results under this 
section. Apply the adjustment factor to the composite emission result.
    (iii) You may apply the adjustment factor only to the hot-start test 
result if your aftertreatment technology does not regenerate during cold 
operation as represented by the cold-start transient duty cycle. If we 
ask for it, you must demonstrate this by engineering analysis or by test 
data.
    (c) If an engine has multiple regeneration strategies, determine and 
apply adjustment factors under this section separately for each type of 
regeneration.

[81 FR 74189, Oct. 25, 2016]



Sec. 1065.690  Buoyancy correction for PM sample media.

    (a) General. Correct PM sample media for their buoyancy in air if 
you weigh them on a balance. The buoyancy correction depends on the 
sample media density, the density of air, and the density of the 
calibration weight used to calibrate the balance. The buoyancy 
correction does not account for the buoyancy of the PM itself, because 
the mass of PM typically accounts for only (0.01 to 0.10)% of the total 
weight. A correction to this small fraction of mass would be at the most 
0.010%.

[[Page 234]]

    (b) PM sample media density. Different PM sample media have 
different densities. Use the known density of your sample media, or use 
one of the densities for some common sampling media, as follows:
    (1) For PTFE-coated borosilicate glass, use a sample media density 
of 2300 kg/m\3\.
    (2) For PTFE membrane (film) media with an integral support ring of 
polymethylpentene that accounts for 95% of the media mass, use a sample 
media density of 920 kg/m\3\.
    (3) For PTFE membrane (film) media with an integral support ring of 
PTFE, use a sample media density of 2144 kg/m\3\.
    (c) Air density. Because a PM balance environment must be tightly 
controlled to an ambient temperature of (22 [1)  deg.C and humidity has 
an insignificant effect on buoyancy correction, air density is primarily 
a function of atmospheric pressure. Therefore you may use nominal 
constant values for temperature and humidity when determining the air 
density of the balance environment in Eq. 1065.690-2.
    (d) Calibration weight density. Use the stated density of the 
material of your metal calibration weight. The example calculation in 
this section uses a density of 8000 kg/m\3\, but you should know the 
density of your weight from the calibration weight supplier or the 
balance manufacturer if it is an internal weight.
    (e) Correction calculation. Correct the PM sample media for buoyancy 
using the following equations:
[GRAPHIC] [TIFF OMITTED] TR28AP14.055

Where:

mcor = PM mass corrected for buoyancy.
muncor = PM mass uncorrected for buoyancy.
rair = density of air in balance environment.
rweight = density of calibration weight used to span balance.
rmedia = density of PM sample media, such as a filter.
[GRAPHIC] [TIFF OMITTED] TR28AP14.056

Where:

pabs = absolute pressure in balance environment.
Mmix = molar mass of air in balance environment.
R = molar gas constant.
Tamb = absolute ambient temperature of balance environment.

[[Page 235]]

[GRAPHIC] [TIFF OMITTED] TR28AP14.057


[[Page 236]]


[GRAPHIC] [TIFF OMITTED] TR28AP14.058


[70 FR 40516, July 13, 2005, as amended at 73 FR 37339, June 30, 2008; 
75 FR 23056, Apr. 30, 2010; 79 FR 23805, Apr. 28, 2014; 81 FR 74191, 
Oct. 25, 2016]



Sec. 1065.695  Data requirements.

    (a) To determine the information we require from engine tests, refer 
to the standard-setting part and request from your Designated Compliance 
Officer the format used to apply for certification or demonstrate 
compliance. We may require different information for different purposes, 
such as for certification applications, approval requests for alternate 
procedures, selective enforcement audits, laboratory audits, production-
line test reports, and field-test reports.
    (b) See the standard-setting part and Sec. 1065.25 regarding 
recordkeeping.
    (c) We may ask you the following about your testing, and we may ask 
you for other information as allowed under the Act:
    (1) What approved alternate procedures did you use? For example:
    (i) Partial-flow dilution for proportional PM.
    (ii) CARB test procedures.
    (iii) ISO test procedures.
    (2) What laboratory equipment did you use? For example, the make, 
model, and description of the following:
    (i) Engine dynamometer and operator demand.
    (ii) Probes, dilution, transfer lines, and sample preconditioning 
components.
    (iii) Batch storage media (such as the bag material or PM filter 
material).
    (3) What measurement instruments did you use? For example, the make, 
model, and description of the following:
    (i) Speed and torque instruments.
    (ii) Flow meters.
    (iii) Gas analyzers.
    (iv) PM balance.
    (4) When did you conduct calibrations and performance checks and 
what were the results? For example, the dates and results of the 
following:
    (i) Linearity verification.
    (ii) Interference checks.
    (iii) Response checks.
    (iv) Leak checks.
    (v) Flow meter checks.
    (5) What engine did you test? For example, the following:
    (i) Manufacturer.
    (ii) Family name on engine label.
    (iii) Model.
    (iv) Model year.
    (v) Identification number.
    (6) How did you prepare and configure your engine for testing? 
Consider the following examples:
    (i) Dates, hours, duty cycle and fuel used for service accumulation.
    (ii) Dates and description of scheduled and unscheduled maintenance.
    (iii) Allowable pressure range of intake restriction.
    (iv) Allowable pressure range of exhaust restriction.
    (v) Charge air cooler volume.
    (vi) Charge air cooler outlet temperature, specified engine 
conditions and location of temperature measurement.
    (vii) Fuel temperature and location of measurement.
    (viii) Any aftertreatment system configuration and description.
    (ix) Any crankcase ventilation configuration and description (e.g., 
open, closed, PCV, crankcase scavenged).
    (x) Number and type of preconditioning cycles.
    (7) How did you test your engine? For example:
    (i) Constant speed or variable speed.

[[Page 237]]

    (ii) Mapping procedure (step or sweep).
    (iii) Continuous or batch sampling for each emission.
    (iv) Raw or dilute sampling; any dilution-air background sampling.
    (v) Duty cycle and test intervals.
    (vi) Cold-start, hot-start, warmed-up running.
    (vii) Absolute pressure, temperature, and dewpoint of intake and 
dilution air.
    (viii) Simulated engine loads, curb idle transmission torque value.
    (ix) Warm-idle speed value.
    (x) Simulated vehicle signals applied during testing.
    (xi) Bypassed governor controls during testing.
    (xii) Date, time, and location of test (e.g., dynamometer laboratory 
identification).
    (xiii) Cooling medium for engine and charge air.
    (xiv) Operating temperatures of coolant, head, and block.
    (xv) Natural or forced cool-down and cool-down time.
    (xvi) Canister loading.
    (8) How did you validate your testing? For example, results from the 
following:
    (i) Duty cycle regression statistics for each test interval.
    (ii) Proportional sampling.
    (iii) Drift.
    (iv) Reference PM sample media in PM-stabilization environment.
    (9) How did you calculate results? For example, results from the 
following:
    (i) Drift correction.
    (ii) Noise correction.
    (iii) ``Dry-to-wet'' correction.
    (iv) NMHC, CH4, and contamination correction.
    (v) NOX humidity correction.
    (vi) Brake-specific emission formulation--total mass divided by 
total work, mass rate divided by power, or ratio of mass to work.
    (vii) Rounding emission results.
    (10) What were the results of your testing? For example:
    (i) Maximum mapped power and speed at maximum power.
    (ii) Maximum mapped torque and speed at maximum torque.
    (iii) For constant-speed engines: no-load governed speed.
    (iv) For constant-speed engines: test torque.
    (v) For variable-speed engines: maximum test speed.
    (vi) Speed versus torque map.
    (vii) Speed versus power map.
    (viii) Brake-specific emissions over the duty cycle and each test 
interval.
    (ix) Brake-specific fuel consumption.
    (11) What fuel did you use? For example:
    (i) Fuel that met specifications of subpart H of this part.
    (ii) Alternate fuel.
    (iii) Oxygenated fuel.
    (12) How did you field test your engine? For example:
    (i) Data from paragraphs (c)(1), (3), (4), (5), and (9) of this 
section.
    (ii) Probes, dilution, transfer lines, and sample preconditioning 
components.
    (iii) Batch storage media (such as the bag material or PM filter 
material).
    (iv) Continuous or batch sampling for each emission.
    (v) Raw or dilute sampling; any dilution air background sampling.
    (vi) Cold-start, hot-start, warmed-up running.
    (vii) Intake and dilution air absolute pressure, temperature, 
dewpoint.
    (viii) Curb idle transmission torque value.
    (ix) Warm idle speed value, any enhanced idle speed value.
    (x) Date, time, and location of test (e.g., identify the testing 
laboratory).
    (xi) Proportional sampling validation.
    (xii) Drift validation.
    (xiii) Operating temperatures of coolant, head, and block.
    (xiv) Vehicle make, model, model year, identification number.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37339, June 30, 2008; 
79 FR 23807, Apr. 28, 2014]



    Subpart H_Engine Fluids, Test Fuels, Analytical Gases and Other 
                          Calibration Standards



Sec. 1065.701  General requirements for test fuels.

    (a) General. For all emission measurements, use test fuels that meet 
the specifications in this subpart, unless

[[Page 238]]

the standard-setting part directs otherwise. Section 1065.10(c)(1) does 
not apply with respect to test fuels. Note that the standard-setting 
parts generally require that you design your emission controls to 
function properly when using commercially available fuels, even if they 
differ from the test fuel. Where we specify multiple grades of a certain 
fuel type (such as diesel fuel with different sulfur concentrations), 
see the standard-setting part to determine which grade to use.
    (b) Fuels meeting alternate specifications. We may allow you to use 
a different test fuel (such as California Phase 2 gasoline) if it does 
not affect your ability to show that your engines would comply with all 
applicable emission standards using the fuel specified in this subpart.
    (c) Fuels not specified in this subpart. If you produce engines that 
run on a type of fuel (or mixture of fuels) that we do not specify in 
this subpart, you must get our written approval to establish the 
appropriate test fuel. See the standard-setting part for provisions 
related to fuels and fuel mixtures not specified in this subpart.
    (1) For engines designed to operate on a single fuel, we will 
generally allow you to use the fuel if you show us all the following 
things are true:
    (i) Show that your engines will use only the designated fuel in 
service.
    (ii) Show that this type of fuel is commercially available.
    (iii) Show that operating the engines on the fuel we specify would 
be inappropriate, as in the following examples:
    (A) The engine will not run on the specified fuel.
    (B) The engine or emission controls will not be durable or work 
properly when operating with the specified fuel.
    (C) The measured emission results would otherwise be substantially 
unrepresentative of in-use emissions.
    (2) For engines that are designed to operate on different fuel 
types, the provisions of paragraphs (c)(1)(ii) and (iii) of this section 
apply with respect to each fuel type.
    (3) For engines that are designed to operate on different fuel types 
as well as continuous mixtures of those fuels, we may require you to 
test with either the worst-case fuel mixture or the most representative 
fuel mixture, unless the standard-setting part specifies otherwise.
    (d) Fuel specifications. Specifications in this section apply as 
follows:
    (1) Measure and calculate values as described in the appropriate 
reference procedure. Record and report final values expressed to at 
least the same number of decimal places as the applicable limit value. 
The right-most digit for each limit value is significant unless 
specified otherwise. For example, for a specified distillation 
temperature of 60  deg.C, determine the test fuel's value to at least 
the nearest whole number.
    (2) The fuel parameters specified in this subpart depend on 
measurement procedures that are incorporated by reference. For any of 
these procedures, you may instead rely upon the procedures identified in 
40 CFR part 80 for measuring the same parameter. For example, we may 
identify different reference procedures for measuring gasoline 
parameters in 40 CFR 80.46.
    (e) Two-stroke fuel/oil mixing. For two-stroke engines, use a fuel/
oil mixture meeting the manufacturer's specifications.
    (f) Service accumulation and field testing fuels. If we do not 
specify a service-accumulation or field-testing fuel in the standard-
setting part, use an appropriate commercially available fuel such as 
those meeting minimum specifications from the following table:

 Table 1 of Sec. 1065.701--Examples of Service-Accumulation and Field-
                              Testing Fuels
------------------------------------------------------------------------
                                                           Reference
          Fuel category               Subcategory        procedure \1\
------------------------------------------------------------------------
Diesel..........................  Light distillate    ASTM D975
                                   and light blends
                                   with residual.
                                  Middle distillate.  ASTM D6985
                                  Biodiesel (B100)..  ASTM D6751
Intermediate and residual fuel..  All...............  See Sec.
                                                       1065.705
Gasoline........................  Automotive          ASTM D4814
                                   gasoline.
                                  Automotive          ASTM D4814
                                   gasoline with
                                   ethanol
                                   concentration up
                                   to 10 volume %..
Alcohol.........................  Ethanol (E51-83)..  ASTM D5798

[[Page 239]]

 
                                  Methanol (M70-M85)  ASTM D5797
Aviation fuel...................  Aviation gasoline.  ASTM D910
                                  Gas turbine.......  ASTM D1655
                                  Jet B wide cut....  ASTM D6615
Gas turbine fuel................  General...........  ASTM D2880
------------------------------------------------------------------------
\1\ ASTM specifications are incorporated by reference in Sec.
  1065.1010.


[70 FR 40516, July 13, 2005, as amended at 73 FR 37339, June 30, 2008; 
73 FR 59341, Oct. 8, 2008; 75 FR 23057, Apr. 30, 2010;79 FR 23807, Apr. 
28, 2014]



Sec. 1065.703  Distillate diesel fuel.

    (a) Distillate diesel fuels for testing must be clean and bright, 
with pour and cloud points adequate for proper engine operation.
    (b) There are three grades of 2 diesel fuel specified for use as a 
test fuel. See the standard-setting part to determine which grade to 
use. If the standard-setting part does not specify which grade to use, 
use good engineering judgment to select the grade that represents the 
fuel on which the engines will operate in use. The three grades are 
specified in the following table:

                 Table 1 of Sec. 1065.703--Test Fuel Specifications for Distillate Diesel Fuel
----------------------------------------------------------------------------------------------------------------
                                                          Ultra low                 High     Reference procedure
             Property                      Unit            sulfur    Low sulfur    sulfur            \1\
----------------------------------------------------------------------------------------------------------------
Cetane Number....................  --..................       40-50       40-50       40-50  ASTM D613.
Distillation range:
    Initial boiling point........  C...................     171-204     171-204     171-204  ASTM D86.
    10 pct. point................  ....................     204-238     204-238     204-238  ASTM D86.
    50 pct. point................  ....................     243-282     243-282     243-282  ASTM D86.
    90 pct. point................  ....................     293-332     293-332     293-332  ASTM D86.
    Endpoint.....................  ....................     321-366     321-366     321-366  ASTM D86.
Gravity..........................  API.................       32-37       32-37       32-37  ASTM D4052.
Total sulfur, ultra low sulfur...  mg/kg...............        7-15  ..........  ..........  See 40 CFR 80.580.
Total sulfur, low and high sulfur  mg/kg...............  ..........     300-500    800-2500  ASTM D2622 or
                                                                                              alternates as
                                                                                              allowed under 40
                                                                                              CFR 80.580.
Aromatics, min. (Remainder shall   g/kg................         100         100         100  ASTM D5186.
 be paraffins, naphthenes, and
 olefins).
Flashpoint, min..................  C...................          54          54          54  ASTM D93.
Kinematic Viscosity..............  cSt.................     2.0-3.2     2.0-3.2     2.0-3.2  ASTM D445.
----------------------------------------------------------------------------------------------------------------
\1\ ASTM procedures are incorporated by reference in Sec. 1065.1010. See Sec. 1065.701(d) for other allowed
  procedures.

    (c) You may use the following nonmetallic additives with distillate 
diesel fuels:
    (1) Cetane improver.
    (2) Metal deactivator.
    (3) Antioxidant, dehazer.
    (4) Rust inhibitor.
    (5) Pour depressant.
    (6) Dye.
    (7) Dispersant.
    (8) Biocide.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37340, June 30, 2008; 
73 FR 59341, Oct. 8, 2008; 75 FR 23057, Apr. 30, 2010; 77 FR 2464, Jan. 
18, 2012;79 FR 23807, Apr. 28, 2014]



Sec. 1065.705  Residual and intermediate residual fuel.

    This section describes the specifications for fuels meeting the 
definition of residual fuel in 40 CFR 80.2, including fuels marketed as 
intermediate fuel. Residual fuels for service accumulation and any 
testing must meet the following specifications:
    (a) The fuel must be a commercially available fuel that is 
representative of the fuel that will be used by the engine in actual 
use.
    (b) The fuel must be free of used lubricating oil. Demonstrate this 
by

[[Page 240]]

showing that the fuel meets at least one of the following 
specifications.
    (1) Zinc is at or below 15 mg per kg of fuel based on the procedures 
specified in IP470, IP501, or ISO 8217 (incorporated by reference in 
Sec. 1065.1010).
    (2) Phosphorus is at or below 15 mg per kg of fuel based on the 
procedures specified in IP500, IP501, or ISO 8217 (incorporated by 
reference in Sec. 1065.1010).
    (3) Calcium is at or below 30 mg per kg of fuel based on the 
procedures specified in IP470, IP501, or ISO 8217 (incorporated by 
reference in Sec. 1065.1010).
    (c) The fuel must meet the specifications for one of the categories 
in the following table:

[[Page 241]]



                             Table 1 of Sec. 1065.705--Service Accumulation and Test Fuel Specifications for Residual Fuel
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                    Category ISO-F-
          Property                  Unit      ------------------------------------------------------------------------------------------    Reference
                                                RMA 30   RMB 30   RMD 80  RME 180  RMF 180  RMG 380  RMH 380  RMK 380  RMH 700  RMK 700    Procedure\1\
--------------------------------------------------------------------------------------------------------------------------------------------------------
Density at 15 C, max........  kg/m\3\........    960.0    975.0    980.0        991.0
                                        991.0            1010.0    991.0   1010.0      ISO
                                                                                   3675 or
                                                                                       ISO
                                                                                     12185
                                                                                      (see
                                                                                      also
                                                                                       ISO
                                                                                    8217).
                                              ----------------------------------------------------------------------------------------------------------
Kinematic viscosity at 50 C,  cSt............        30.0           80.0        180.0
 max.
                                        380.0
                                            700.0                    ISO
                                                                   3104.
Flash point, min............  C..............         60              60         60
                                         60
                                              60                     ISO
                                                                    2719
                                                                    (see
                                                                    also
                                                                     ISO
                                                                  8217).
                                              ----------------------------------------------------------------------------------------------------------
Pour point (upper):
    Winter quality, max.....  C..............        0       24       30         30
                                         30
                                              30                     ISO
                                                                   3016.
    Summer quality, max.....  ...............        6       24       30         30
                                         30
                                              30
                                              ----------------------------------------------------------------------------------------------------------
Carbon residue, max.........  (kg/kg) %......         10              14       15       20       18       22              22             ISO 10370.
                                              ----------------------------------------------------------------------------------------------------------
Ash, max....................  (kg/kg) %......        0.10           0.10     0.10     0.15        0.15
                                             0.15                    ISO
                                                                   6245.
                                              ----------------------------------------------------------------------------------------------------------
Water, max..................  (m\3\/m\3\) %..         0.5            0.5         0.5
                                         0.5
                                             0.5                     ISO
                                                                   3733.
                                              ----------------------------------------------------------------------------------------------------------
Sulfur, max.................  (kg/kg) %......        3.50           4.00        4.50
                                        4.50
                                             4.50                    ISO
                                                                 8754 or
                                                                     ISO
                                                                   14596
                                                                    (see
                                                                    also
                                                                     ISO
                                                                  8217).
                                              ----------------------------------------------------------------------------------------------------------
Vanadium, max...............  mg/kg..........         150            350      200      500      300      600             600             ISO 14597 or IP
                                                                                                                                          501 or IP 470
                                                                                                                                          (see also ISO
                                                                                                                                          8217).
                                              ----------------------------------------------------------------------------------------------------------
Total sediment potential,     (kg/kg) %......        0.10           0.10        0.10
 max.
                                        0.10
                                             0.10                    ISO
                                                                 10307-2
                                                                    (see
                                                                    also
                                                                     ISO
                                                                  8217).
                                              ----------------------------------------------------------------------------------------------------------
Aluminum plus silicon, max..  mg/kg..........         80              80         80
                                         80
                                              80                     ISO
                                                                   10478
                                                                   or IP
                                                                  501 or
                                                                  IP 470
                                                                    (see
                                                                    also
                                                                     ISO
                                                                 8217:20
                                                                    12).
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ ISO procedures are incorporated by reference in Sec. 1065.1010. See Sec. 1065.701(d) for other allowed procedures.


[79 FR 23808, Apr. 28, 2014]

[[Page 242]]



Sec. 1065.710  Gasoline.

    (a) This section specifies test fuel properties for gasoline with 
ethanol (low-level blend only) and for gasoline without ethanol. Note 
that the ``fuel type'' for the fuels specified in paragraphs (b) and (c) 
of this section is considered to be gasoline. In contrast, fuels with 
higher ethanol concentrations, such as fuel containing 82 percent 
ethanol, are considered to be ethanol fuels rather than gasoline. We 
specify some test fuel parameters that apply uniquely for low-
temperature testing and for testing at altitudes above 1,219 m. For all 
other testing, use the test fuel parameters specified for general 
testing. Unless the standard-setting part specifies otherwise, use the 
fuel specified in paragraph (c) of this section for general testing.
    (b) The following specifications apply for a blended gasoline test 
fuel that has nominally 10% ethanol (commonly called E10 test fuel):
    (1) Prepare the blended test fuel from typical refinery gasoline 
blending components. You may not use pure compounds, except as follows:
    (i) You may use neat ethanol as a blendstock.
    (ii) You may adjust the test fuel's vapor pressure by adding butane.
    (iii) You may adjust the test fuel's benzene content by adding 
benzene.
    (iv) You may adjust the test fuel's sulfur content by adding sulfur 
compounds that are representative of those found with in-use fuels.
    (2) Table 1 of this section identifies limit values consistent with 
the units in the reference procedure for each fuel property. These 
values are generally specified in international units. Values presented 
in parentheses are for information only. Table 1 follows:

                               Table 1 of Sec. 1065.710--Test Fuel Specifications for a Low-Level Ethanol-Gasoline Blend
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         Specification
                                                            ----------------------------------------------------------------------  Reference procedure
              Property                        Unit                                      Low-temperature                                     \1\
                                                                 General testing            testing         High altitude testing
--------------------------------------------------------------------------------------------------------------------------------------------------------
Antiknock Index (R + M)/2..........  ......................                  87.0--88.4 \2\                 87.0 Minimum.........  ASTM D2699 and D2700.
                                                            ----------------------------------------------------------------------
Sensitivity (R-M)..................  ......................                               7.5 Minimum                              ASTM D2699 and D2700.
                                                            ----------------------------------------------------------------------
Dry Vapor Pressure Equivalent        kPa (psi).............  60.0-63.4.............  77.2-81.4............  52.4-55.2............  ASTM D5191.
 (DVPE) \3,4\.                                               (8.7-9.2).............  (11.2-11.8)..........  (7.6-8.0)............
Distillation \4\...................  C ( F)................  49-60.................  43-54................  49-60................  ASTM D86.
10% evaporated.....................                          (120-140).............  (110-130)............  (120-140)............
                                                            ----------------------------------------------------------------------
50% evaporated.....................  C ( F)................                            88-99 (190-210).
90% evaporated.....................  C ( F)................                           157-168 (315-335).
Evaporated final boiling point.....  C ( F)................                           193-216 (380-420).
Residue............................  milliliter............                              2.0 Maximum.
Total Aromatic Hydrocarbons........  volume %..............                                21.0-25.0                               ASTM D5769.
C6 Aromatics (benzene).............  volume %..............                                0.5-0.7.
C7 Aromatics (toluene).............  volume %..............                                5.2-6.4.
C8 Aromatics.......................  volume %..............                                5.2-6.4.
C9 Aromatics.......................  volume %..............                                5.2-6.4.
C10 + Aromatics....................  volume %..............                                4.4-5.6.
Olefins \5\........................  mass %................                                4.0-10.0                                ASTM D6550.
Ethanol blended....................  volume %..............                                9.6-10.0                                See paragraph (b)(3)
                                                                                                                                    of this section.
Ethanol confirmatory \6\...........  volume %..............                                9.4-10.2                                ASTM D4815 or D5599.
Total Content of Oxygenates Other    volume %..............                               0.1 Maximum                              ASTM D4815 or D5599.
 than Ethanol \6\.
Sulfur.............................  mg/kg.................                                8.0-11.0                                ASTM D2622, D5453 or
                                                                                                                                    D7039.
Lead...............................  g/liter...............                             0.0026 Maximum                             ASTM D3237.
Phosphorus.........................  g/liter...............                             0.0013 Maximum                             ASTM D3231.
Copper Corrosion...................  ......................                              No. 1 Maximum                             ASTM D130.
Solvent-Washed Gum Content.........  mg/100 milliliter.....                               3.0 Maximum                              ASTM D381.
Oxidation Stability................  minute................                              1000 Minimum                              ASTM D525.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ ASTM procedures are incorporated by reference in Sec. 1065.1010. See Sec. 1065.701(d) for other allowed procedures.
\2\ Octane specifications apply only for testing related to exhaust emissions. For engines or vehicles that require the use of premium fuel, as
  described in paragraph (d) of this section, the adjusted specification for antiknock index is a minimum value of 91.0; no maximum value applies. All
  other specifications apply for this high-octane fuel.

[[Page 243]]

 
\3\ Calculate dry vapor pressure equivalent, DVPE, based on the measured total vapor pressure, pT, using the following equation: DVPE (kPa) = 0.956
  [middot] pT--2.39 or DVPE (psi) = 0.956 [middot] pT--0.347. DVPE is intended to be equivalent to Reid Vapor Pressure using a different test method.
\4\ Parenthetical values are shown for informational purposes only.
\5\ The reference procedure prescribes measurement of olefin concentration in mass %. Multiply this result by 0.857 and round to the first decimal place
  to determine the olefin concentration in volume %.
\6\ ASTM D5599 prescribes concentration measurements for ethanol and other oxygenates in mass %. Convert results to volume % as specified in Section
  14.3 of ASTM D4815.

    (3) The ethanol-blended specification in Table 1 of this section is 
based on the volume % ethanol content of the fuel as determined during 
blending by the fuel supplier and as stated by the supplier at the time 
of fuel delivery. Use good engineering judgment to determine the volume 
% of ethanol based on the volume of each blendstock. We recommend using 
a flow-based or gravimetric procedure that has an accuracy and 
repeatability of [0.1%.
    (c) The specifications of this paragraph (c) apply for testing with 
neat gasoline. This is sometimes called indolene or E0 test fuel. 
Gasoline for testing must have octane values that represent commercially 
available fuels for the appropriate application. Test fuel 
specifications apply as follows:

                   Table 2 of Sec. 1065.710--Test Fuel Specifications for Neat (E0) Gasoline
----------------------------------------------------------------------------------------------------------------
                                                                   Specification
                                                     ----------------------------------------      Reference
            Property                     Unit                               Low-temperature      procedure \1\
                                                        General testing         testing
----------------------------------------------------------------------------------------------------------------
Distillation Range:
    Evaporated initial boiling    C.................  24-35\2\..........  24-36.............  ASTM D86
     point.
    10% evaporated..............  ..................  49-57.............  37-48.............
    50% evaporated..............  ..................  93-110............  82-101............
    90% evaporated..............  ..................  149-163...........  158-174...........
    Evaporated final boiling      ..................  Maximum, 213......  Maximum, 212......
     point.
Hydrocarbon composition:
    Olefins.....................  volume %..........  Maximum, 10.......  Maximum, 17.5.....  ASTM D1319
    Aromatics...................  ..................  Maximum, 35.......  Maximum, 30.4.....
    Saturates...................  ..................  Remainder.........  Remainder.........
Lead............................  g/liter...........  Maximum, 0.013....  Maximum, 0.013....  ASTM D3237
Phosphorous.....................  g/liter...........  Maximum, 0.0013...  Maximum, 0.005....  ASTM D3231
Total sulfur....................  mg/kg.............  Maximum, 80.......  Maximum, 80.......  ASTM D2622
Dry vapor pressure equivalent     kPa (psi).........  60.0-63.4 \2,4\     77.2-81.4 (11.2-    ASTM D5191
 \3\.                                                  (8.7-9.2).          11.8).
----------------------------------------------------------------------------------------------------------------
\1\ ASTM procedures are incorporated by reference in Sec. 1065.1010. See Sec. 1065.701(d) for other allowed
  procedures.
\2\ For testing at altitudes above 1219 m, the specified initial boiling point range is (23.9 to 40.6) C and the
  specified volatility range is (52.0 to 55.2) kPa ((7.5 to 8.0) psi).
\3\ Calculate dry vapor pressure equivalent, DVPE, based on the measured total vapor pressure, pT, in kPa using
  the following equation: DVPE (kPa) = 0.956 [middot] pT-2.39 or DVPE (psi) = 0.956 [middot] pT-0.347. DVPE is
  intended to be equivalent to Reid Vapor Pressure using a different test method.
\4\ For testing unrelated to evaporative emissions, the specified range is (55.2 to 63.4) kPa ((8.0 to 9.2)
  psi).

    (d) Use the high-octane gasoline specified in paragraph (b) of this 
section only for engines or vehicles for which the manufacturer 
conditions the warranty on the use of premium gasoline.

[79 FR 23809, Apr. 28, 2014, as amended at 80 FR 9119, Feb. 19, 2015]



Sec. 1065.715  Natural gas.

    (a) Except as specified in paragraph (b) of this section, natural 
gas for testing must meet the specifications in the following table:

  Table 1 of Sec. 1065.715--Test Fuel Specifications for Natural Gas
------------------------------------------------------------------------
            Property                             Value \1\
------------------------------------------------------------------------
Methane, CH4....................  Minimum, 0.87 mol/mol.
Ethane, C2H6....................  Maximum, 0.055 mol/mol.
Propane, C3H8...................  Maximum, 0.012 mol/mol.
Butane, C4H10...................  Maximum, 0.0035 mol/mol.
Pentane, C5H12..................  Maximum, 0.0013 mol/mol.
C6 and higher...................  Maximum, 0.001 mol/mol.
Oxygen..........................  Maximum, 0.001 mol/mol.

[[Page 244]]

 
Inert gases (sum of CO2 and N2).  Maximum, 0.051 mol/mol.
------------------------------------------------------------------------
\1\ Demonstrate compliance with fuel specifications based on the
  reference procedures in ASTM D1945 (incorporated by reference in Sec.
   1065.1010), or on other measurement procedures using good engineering
  judgment. See Sec. 1065.701(d) for other allowed procedures.

    (b) In certain cases you may use test fuel not meeting the 
specifications in paragraph (a) of this section, as follows:
    (1) You may use fuel that your in-use engines normally use, such as 
pipeline natural gas.
    (2) You may use fuel meeting alternate specifications if the 
standard-setting part allows it.
    (3) You may ask for approval to use fuel that does not meet the 
specifications in paragraph (a) of this section, but only if using the 
fuel would not adversely affect your ability to demonstrate compliance 
with the applicable standards.
    (c) When we conduct testing using natural gas, we will use fuel that 
meets the specifications in paragraph (a) of this section.
    (d) At ambient conditions, natural gas must have a distinctive odor 
detectable down to a concentration in air not more than one-fifth the 
lower flammable limit.

[73 FR 37342, June 30, 2008, as amended at 79 FR 23811, Apr. 28, 2014]



Sec. 1065.720  Liquefied petroleum gas.

    (a) Except as specified in paragraph (b) of this section, liquefied 
petroleum gas for testing must meet the specifications in the following 
table:

                Table 1 of Sec. 1065.720--Test Fuel Specifications for Liquefied Petroleum Gas
----------------------------------------------------------------------------------------------------------------
                 Property                              Value                     Reference procedure \1\
----------------------------------------------------------------------------------------------------------------
Propane, C3H8............................  Minimum, 0.85 m\3\/m\3\.....  ASTM D2163.
Vapor pressure at 38 C...................  Maximum, 1400 kPa...........  ASTM D1267or D2598.\2\
Volatility residue (evaporated             Maximum, -38 C..............  ASTM D1837.
 temperature, 35 C).
Butanes..................................  Maximum, 0.05 m\3\/m\3\.....  ASTM D2163.
Butenes..................................  Maximum, 0.02 m\3\/m\3\.....  ASTM D2163.
Pentenes and heavier.....................  Maximum, 0.005 m\3\/m\3\....  ASTM D2163.
Propene..................................  Maximum, 0.1 m\3\/m\3\......  ASTM D2163.
Residual matter (residue on evaporation    Maximum, 0.05 ml pass\3\....  ASTM D2158.
 of 100 ml oil stain observation).
Corrosion, copper strip..................  Maximum, No. 1..............  ASTM D1838.
Sulfur...................................  Maximum, 80 mg/kg...........  ASTM D2784.
Moisture content.........................  pass........................  ASTM D2713.
----------------------------------------------------------------------------------------------------------------
\1\ ASTM procedures are incorporated by reference in Sec. 1065.1010. See Sec. 1065.701(d) for other allowed
  procedures.
\2\ If these two test methods yield different results, use the results from ASTM D1267.
\3\ The test fuel must not yield a persistent oil ring when you add 0.3 ml of solvent residue mixture to a
  filter paper in 0.1 ml increments and examine it in daylight after two minutes.

    (b) In certain cases you may use test fuel not meeting the 
specifications in paragraph (a) of this section, as follows:
    (1) You may use fuel that your in-use engines normally use, such as 
commercial-quality liquefied petroleum gas.
    (2) You may use fuel meeting alternate specifications if the 
standard-setting part allows it.
    (3) You may ask for approval to use fuel that does not meet the 
specifications in paragraph (a) of this section, but only if using the 
fuel would not adversely affect your ability to demonstrate compliance 
with the applicable standards.
    (c) When we conduct testing using liquefied petroleum gas, we will 
use fuel that meets the specifications in paragraph (a) of this section.
    (d) At ambient conditions, liquefied petroleum gas must have a 
distinctive odor detectable down to a concentration in air not more than 
one-fifth the lower flammable limit.

[73 FR 37342, June 30, 2008, as amended at 79 FR 23811, Apr. 28, 2014]

[[Page 245]]



Sec. 1065.725  High-level ethanol-gasoline blends.

    For testing vehicles capable of operating on a high-level ethanol-
gasoline blend, create a test fuel as follows:
    (a) Add ethanol to an E10 fuel meeting the specifications described 
in Sec. 1065.710 until the ethanol content of the blended fuel is 
between 80 and 83 volume %.
    (b) You may alternatively add ethanol to a gasoline base fuel with 
no ethanol if you can demonstrate that such a base fuel blended with the 
proper amount of ethanol would meet all the specifications for E10 test 
fuel described in Sec. 1065.710, other than the ethanol content.
    (c) The ethanol used for blending must be either denatured ethanol 
meeting the specifications in 40 CFR 80.1610, or fuel-grade ethanol with 
no denaturant. Account for the volume of any denaturant when calculating 
volumetric percentages.
    (d) The blended test fuel must have a dry vapor pressure equivalent 
between 41.5 and 45.1 kPa (6.0 and 6.5 psi) when measured using the 
procedure specified in Sec. 1065.710. You may add commercial grade 
butane as needed to meet this specification.

[79 FR 23811, Apr. 28, 2014]



Sec. 1065.735  Diesel exhaust fluid.

    (a) Use commercially available diesel exhaust fluid that represents 
the product that will be used in your in-use engines.
    (b) Diesel exhaust fluid for testing must generally conform to the 
specifications referenced in the definition of ``diesel exhaust fluid'' 
in Sec. 1065.1001. Use marine-grade diesel exhaust fluid only for 
marine engines.

[81 FR 74191, Oct. 25, 2016]



Sec. 1065.740  Lubricants.

    (a) Use commercially available lubricating oil that represents the 
oil that will be used in your engine in use.
    (b) You may use lubrication additives, up to the levels that the 
additive manufacturer recommends.



Sec. 1065.745  Coolants.

    (a) You may use commercially available antifreeze mixtures or other 
coolants that will be used in your engine in use.
    (b) For laboratory testing of liquid-cooled engines, you may use 
water with or without rust inhibitors.
    (c) For coolants allowed in paragraphs (a) and (b) of this section, 
you may use rust inhibitors and additives required for lubricity, up to 
the levels that the additive manufacturer recommends.



Sec. 1065.750  Analytical gases.

    Analytical gases must meet the accuracy and purity specifications of 
this section, unless you can show that other specifications would not 
affect your ability to show that you comply with all applicable emission 
standards.
    (a) Subparts C, D, F, and J of this part refer to the following gas 
specifications:
    (1) Use purified gases to zero measurement instruments and to blend 
with calibration gases. Use gases with contamination no higher than the 
highest of the following values in the gas cylinder or at the outlet of 
a zero-gas generator:
    (i) 2% contamination, measured relative to the flow-weighted mean 
concentration expected at the standard. For example, if you would expect 
a flow-weighted CO concentration of 100.0 [micro] mol/mol, then you 
would be allowed to use a zero gas with CO contamination less than or 
equal to 2.000 [micro] mol/mol.
    (ii) Contamination as specified in the following table:

                    Table 1 of Sec. 1065.750--General Specifications for Purified Gases \1\
----------------------------------------------------------------------------------------------------------------
               Constituent                           Purified air                        Purified N2
----------------------------------------------------------------------------------------------------------------
THC (C1-equivalent)......................  <=0.05 [micro] mol/mol..........  <=0.05 [micro] mol/mol.
CO.......................................  <=1 [micro] mol/mol.............  <=1 [micro] mol/mol.
CO2......................................  <=10 [micro] mol/mol............  <=10 [micro] mol/mol.
O2.......................................  0.205 to 0.215 mol/mol..........  <=2 [micro] mol/mol.
NOX......................................  <=0.02 [micro] mol/mol..........  <=0.02 [micro] mol/mol.

[[Page 246]]

 
N2O\2\...................................  <=0.02 [micro] mol/mol..........  <=0.02 [micro] mol/mol.
----------------------------------------------------------------------------------------------------------------
\1\ We do not require these levels of purity to be NIST-traceable.
\2\ The N2O limit applies only if the standard-setting part requires you to report N2O or certify to an N2O
  standard.

    (2) Use the following gases with a FID analyzer:
    (i) FID fuel. Use FID fuel with a stated H2 concentration 
of (0.39 to 0.41) mol/mol, balance He or N2, and a stated 
total hydrocarbon concentration of 0.05 [micro] mol/mol or less. For GC-
FIDs that measure methane (CH4) using a FID fuel that is 
balance N2, perform the CH4 measurement as 
described in SAE J1151 (incorporated by reference in Sec. 1065.1010).
    (ii) FID burner air. Use FID burner air that meets the 
specifications of purified air in paragraph (a)(1) of this section. For 
field testing, you may use ambient air.
    (iii) FID zero gas. Zero flame-ionization detectors with purified 
gas that meets the specifications in paragraph (a)(1) of this section, 
except that the purified gas O2 concentration may be any 
value. Note that FID zero balance gases may be any combination of 
purified air and purified nitrogen. We recommend FID analyzer zero gases 
that contain approximately the expected flow-weighted mean concentration 
of O2 in the exhaust sample during testing.
    (iv) FID propane span gas. Span and calibrate THC FID with span 
concentrations of propane, C3H8. Calibrate on a 
carbon number basis of one (C1). For example, if you use a 
C3H8 span gas of concentration 200 [micro] mol/
mol, span a FID to respond with a value of 600 [micro] mol/mol. Note 
that FID span balance gases may be any combination of purified air and 
purified nitrogen. We recommend FID analyzer span gases that contain 
approximately the flow-weighted mean concentration of O2 
expected during testing. If the expected O2 concentration in 
the exhaust sample is zero, we recommend using a balance gas of purified 
nitrogen.
    (v) FID CH4 span gas. If you always span and calibrate a 
CH4 FID with a nonmethane cutter, then span and calibrate the 
FID with span concentrations of CH4. Calibrate on a carbon 
number basis of one (C1). For example, if you use a 
CH4 span gas of concentration 200 [micro] mol/mol, span a FID 
to respond with a value of 200 [micro] mol/mol. Note that FID span 
balance gases may be any combination of purified air and purified 
nitrogen. We recommend FID analyzer span gases that contain 
approximately the expected flow-weighted mean concentration of 
O2 in the exhaust sample during testing. If the expected 
O2 concentration in the exhaust sample is zero, we recommend 
using a balance gas of purified nitrogen.
    (3) Use the following gas mixtures, with gases traceable within [1% 
of the NIST-accepted value or other gas standards we approve:
    (i) CH4, balance purified air and/or N2 (as 
applicable).
    (ii) C2H6, balance purified air and/or 
N2 (as applicable).
    (iii) C3H8, balance purified air and/or 
N2 (as applicable).
    (iv) CO, balance purified N2.
    (v) CO2, balance purified N2.
    (vi) NO, balance purified N2.
    (vii) NO2, balance purified air.
    (viii) O2, balance purified N2.
    (ix) C3H8, CO, CO2, NO, balance 
purified N2.
    (x) C3H8, CH4, CO, CO2, 
NO, balance purified N2.
    (xi) N2O, balance purified air and/or N2 (as 
applicable).
    (xii) CH4, C2H6, balance purified 
air and/or N2 (as applicable).
    (xiii) CH4, CH2O, CH2O2, 
C2H2, C2H4, 
C2H4O, C2H6, 
C3H8, C3H6, CH4O, 
and C4H10. You may omit individual gas 
constituents from this gas mixture. If your gas mixture contains 
oxygenated hydrocarbon, your gas mixture must be in balance purified 
N2, otherwise you may use balance purified air.
    (4) You may use gases for species other than those listed in 
paragraph (a)(3) of this section (such as methanol in air, which you may 
use to determine response factors), as long as they are

[[Page 247]]

traceable to within [3% of the NIST-accepted value or other similar 
standards we approve, and meet the stability requirements of paragraph 
(b) of this section.
    (5) You may generate your own calibration gases using a precision 
blending device, such as a gas divider, to dilute gases with purified 
N2 or purified air. If your gas divider meets the 
specifications in Sec. 1065.248, and the gases being blended meet the 
requirements of paragraphs (a)(1) and (3) of this section, the resulting 
blends are considered to meet the requirements of this paragraph (a).
    (b) Record the concentration of any calibration gas standard and its 
expiration date specified by the gas supplier.
    (1) Do not use any calibration gas standard after its expiration 
date, except as allowed by paragraph (b)(2) of this section.
    (2) Calibration gases may be relabeled and used after their 
expiration date as follows:
    (i) Alcohol/carbonyl calibration gases used to determine response 
factors according to subpart I of this part may be relabeled as 
specified in subpart I of this part.
    (ii) Other gases may be relabeled and used after the expiration date 
only if we approve it in advance.
    (c) Transfer gases from their source to analyzers using components 
that are dedicated to controlling and transferring only those gases. For 
example, do not use a regulator, valve, or transfer line for zero gas if 
those components were previously used to transfer a different gas 
mixture. We recommend that you label regulators, valves, and transfer 
lines to prevent contamination. Note that even small traces of a gas 
mixture in the dead volume of a regulator, valve, or transfer line can 
diffuse upstream into a high-pressure volume of gas, which would 
contaminate the entire high-pressure gas source, such as a compressed-
gas cylinder.
    (d) To maintain stability and purity of gas standards, use good 
engineering judgment and follow the gas standard supplier's 
recommendations for storing and handling zero, span, and calibration 
gases. For example, it may be necessary to store bottles of condensable 
gases in a heated environment.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37343, June 30, 2008; 
74 FR 56518, Oct. 30, 2009; 75 FR 68465, Nov. 8, 2010; 76 FR 57467, 
Sept. 15, 2011; 79 FR 23811, Apr. 28, 2014; 81 FR 74191, Oct. 25, 2016]



Sec. 1065.790  Mass standards.

    (a) PM balance calibration weights. Use PM balance calibration 
weights that are certified as NIST-traceable within 0.1% uncertainty. 
Calibration weights may be certified by any calibration lab that 
maintains NIST-traceability. Make sure your highest calibration weight 
has no greater than ten times the mass of an unused PM-sample medium.
    (b) Dynamometer calibration weights. [Reserved]

[70 FR 40516, July 13, 2005, as amended at 76 FR 57467, Sept. 15, 2011]



                 Subpart I_Testing With Oxygenated Fuels



Sec. 1065.801  Applicability.

    (a) This subpart applies for testing with oxygenated fuels. Unless 
the standard-setting part specifies otherwise, the requirements of this 
subpart do not apply for fuels that contain less than 25% oxygenated 
compounds by volume. For example, you generally do not need to follow 
the requirements of this subpart for tests performed using a fuel 
containing 10% ethanol and 90% gasoline, but you must follow these 
requirements for tests performed using a fuel containing 85% ethanol and 
15% gasoline.
    (b) Section 1065.805 applies for all other testing that requires 
measurement of any alcohols or carbonyls.
    (c) This subpart specifies sampling procedures and calculations that 
are different than those used for non-oxygenated fuels. All other test 
procedures of this part 1065 apply for testing with oxygenated fuels.



Sec. 1065.805  Sampling system.

    (a) Dilute engine exhaust, and use batch sampling to collect 
proportional flow-weighted dilute samples of the applicable alcohols and 
carbonyls. You

[[Page 248]]

may not use raw sampling for alcohols and carbonyls.
    (b) You may collect background samples for correcting dilution air 
for background concentrations of alcohols and carbonyls.
    (c) Maintain sample temperatures within the dilution tunnel, probes, 
and sample lines high enough to prevent aqueous condensation up to the 
point where a sample is collected to prevent loss of the alcohols and 
carbonyls by dissolution in condensed water. Use good engineering 
judgment to ensure that surface reactions of alcohols and carbonyls do 
not occur, as surface decomposition of methanol has been shown to occur 
at temperatures greater than 120  deg.C in exhaust from methanol-fueled 
engines.
    (d) You may bubble a sample of the exhaust through water to collect 
alcohols for later analysis. You may also use a photoacoustic analyzer 
to quantify ethanol and methanol in an exhaust sample as described in 
Sec. 1065.269.
    (e) Sample the exhaust through cartridges impregnated with 2,4-
dinitrophenylhydrazine to collect carbonyls for later analysis. If the 
standard-setting part specifies a duty cycle that has multiple test 
intervals (such as multiple engine starts or an engine-off soak phase), 
you may proportionally collect a single carbonyl sample for the entire 
duty cycle. For example, if the standard-setting part specifies a six-
to-one weighting of hot-start to cold-start emissions, you may collect a 
single carbonyl sample for the entire duty cycle by using a hot-start 
sample flow rate that is six times the cold-start sample flow rate.
    (f) You may sample alcohols or carbonyls using ``California Non-
Methane Organic Gas Test Procedures'' (incorporated by reference in 
Sec. 1065.1010). If you use this method, follow its calculations to 
determine the mass of the alcohol/carbonyl in the exhaust sample, but 
follow subpart G of this part for all other calculations (40 CFR part 
1066, subpart G, for vehicle testing).
    (g) Use good engineering judgment to sample other oxygenated 
hydrocarbon compounds in the exhaust.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37343, June 30, 2008; 
79 FR 23812, Apr. 28, 2014]



Sec. 1065.845  Response factor determination.

    Since FID analyzers generally have an incomplete response to 
alcohols and carbonyls, determine each FID analyzer's alcohol/carbonyl 
response factor (RFOHCi[THC-FID]) after FID optimization to 
subtract those responses from the FID reading. Use the most recently 
determined alcohol/carbonyl response factors to compensate for alcohol/
carbonyl response. You are not required to determine the response factor 
for a compound unless you will subtract its response to compensate for a 
response.
    (a) You may generate response factors as described in paragraph (b) 
of this section, or you may use the following default response factors, 
consistent with good engineering judgment:

 Table 1 of Sec. 1065.845--Default Values for THC FID Response Factor
              Relative to Propane on a C1-Equivalent Basis
------------------------------------------------------------------------
                                                         Response factor
                        Compound                               (RF)
------------------------------------------------------------------------
acetaldehyde...........................................             0.50
ethanol................................................             0.75
formaldehyde...........................................             0.00
methanol...............................................             0.63
propanol...............................................             0.85
------------------------------------------------------------------------

    (b) Determine the alcohol/carbonyl response factors as follows:
    (1) Select a C3H8 span gas that meets the 
specifications of Sec. 1065.750. Note that FID zero and span balance 
gases may be any combination of purified air or purified nitrogen that 
meets the specifications of Sec. 1065.750. We recommend FID analyzer 
zero and span gases that contain approximately the flow-weighted mean 
concentration of O2 expected during testing. Record the 
C3H8 concentration of the gas.
    (2) Select or prepare an alcohol/carbonyl calibration gas that meets 
the specifications of Sec. 1065.750 and has a concentration typical of 
the peak concentration expected at the hydrocarbon standard. Record the 
calibration concentration of the gas.
    (3) Start and operate the FID analyzer according to the 
manufacturer's instructions.
    (4) Confirm that the FID analyzer has been calibrated using 
C3H8. Calibrate on a carbon number basis of one 
(C1).

[[Page 249]]

For example, if you use a C3H8 span gas of 
concentration 200 [micro] mol/mol, span the FID to respond with a value 
of 600 [micro] mol/mol.
    (5) Zero the FID. Note that FID zero and span balance gases may be 
any combination of purified air or purified nitrogen that meets the 
specifications of Sec. 1065.750. We recommend FID analyzer zero and 
span gases that contain approximately the flow-weighted mean 
concentration of O2 expected during testing.
    (6) Span the FID with the C3H8 span gas that 
you selected under paragraph (a)(1) of this section.
    (7) Introduce at the inlet of the FID analyzer the alcohol/carbonyl 
calibration gas that you selected under paragraph (a)(2) of this 
section.
    (8) Allow time for the analyzer response to stabilize. Stabilization 
time may include time to purge the analyzer and to account for its 
response.
    (9) While the analyzer measures the alcohol/carbonyl concentration, 
record 30 seconds of sampled data. Calculate the arithmetic mean of 
these values.
    (10) Divide the mean measured concentration by the recorded span 
concentration of the alcohol/carbonyl calibration gas on a 
C1-equivalent basis. The result is the FID analyzer's 
response factor for alcohol/carbonyl, RFOHCi[THC-FID] on a 
C1-equivalent basis.
    (c) Alcohol/carbonyl calibration gases must remain within [2% of the 
labeled concentration. You must demonstrate the stability based on a 
quarterly measurement procedure with a precision of [2% percent or 
another method that we approve. Your measurement procedure may 
incorporate multiple measurements. If the true concentration of the gas 
changes deviates by more than [2%, but less than [10%, the gas may be 
relabeled with the new concentration.

[79 FR 23812, Apr. 28, 2014, as amended at 79 FR 36658, June 30, 2014]



Sec. 1065.850  Calculations.

    Use the calculations specified in Sec. 1065.665 to determine THCE 
or NMHCE and the calculations specified in 40 CFR 1066.635 to determine 
NMOG.

[79 FR 23813, Apr. 28, 2014]



    Subpart J_Field Testing and Portable Emission Measurement Systems



Sec. 1065.901  Applicability.

    (a) Field testing. This subpart specifies procedures for field-
testing engines to determine brake-specific emissions using portable 
emission measurement systems (PEMS). These procedures are designed 
primarily for in-field measurements of engines that remain installed in 
vehicles or equipment in the field. Field-test procedures apply to your 
engines only as specified in the standard-setting part.
    (b) Laboratory testing. You may use PEMS for any testing in a 
laboratory or similar environment without restriction or prior approval 
if the PEMS meets all applicable specifications for laboratory testing. 
You may also use PEMS for any testing in a laboratory or similar 
environment if we approve it in advance, subject to the following 
provisions:
    (1) Follow the laboratory test procedures specified in this part 
1065, according to Sec. 1065.905(e).
    (2) Do not apply any PEMS-related field-testing adjustments or 
measurement allowances to laboratory emission results or standards.
    (3) Do not use PEMS for laboratory measurements if it prevents you 
from demonstrating compliance with the applicable standards. Some of the 
PEMS requirements in this part 1065 are less stringent than the 
corresponding laboratory requirements. Depending on actual PEMS 
performance, you might therefore need to account for some additional 
measurement uncertainty when using PEMS for laboratory testing. If we 
ask, you must show us by engineering analysis that any additional 
measurement uncertainty due to your use of PEMS for laboratory testing 
is offset by the extent to which your engine's emissions are below the 
applicable standards. For example, you might show that PEMS versus 
laboratory uncertainty represents 5% of the standard, but your engine's 
deteriorated emissions are at least 20% below the standard for each 
pollutant.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37344, June 30, 2008]

[[Page 250]]



Sec. 1065.905  General provisions.

    (a) General. Unless the standard-setting part specifies deviations 
from the provisions of this subpart, field testing and laboratory 
testing with PEMS must conform to the provisions of this subpart. Use 
good engineering judgment when testing with PEMS to ensure proper 
function of the instruments under test conditions. For example, this may 
require additional maintenance or calibration for field testing or may 
require verification after moving the PEMS unit.
    (b) Field-testing scope. Field testing conducted under this subpart 
may include any normal in-use operation of an engine.
    (c) Field testing and the standard-setting part. This subpart J 
specifies procedures for field-testing various categories of engines. 
See the standard-setting part for specific provisions for a particular 
type of engine. Before using this subpart's procedures for field 
testing, read the standard-setting part to answer at least the following 
questions:
    (1) How many engines must I test in the field?
    (2) How many times must I repeat a field test on an individual 
engine?
    (3) How do I select vehicles for field testing?
    (4) What maintenance steps may I take before or between tests?
    (5) What data are needed for a single field test on an individual 
engine?
    (6) What are the limits on ambient conditions for field testing? 
Note that the ambient condition limits in Sec. 1065.520 do not apply 
for field testing. Field testing may occur at any ambient temperature, 
pressure, and humidity unless otherwise specified in the standard-
setting part.
    (7) Which exhaust constituents do I need to measure?
    (8) How do I account for crankcase emissions?
    (9) Which engine and ambient parameters do I need to measure?
    (10) How do I process the data recorded during field testing to 
determine if my engine meets field-testing standards? How do I determine 
individual test intervals? Note that ``test interval'' is defined in 
subpart K of this part 1065.
    (11) Should I warm up the test engine before measuring emissions, or 
do I need to measure cold-start emissions during a warm-up segment of 
in-use operation?
    (12) Do any unique specifications apply for test fuels?
    (13) Do any special conditions invalidate parts of a field test or 
all of a field test?
    (14) Does any special measurement allowance apply to field-test 
emission results or standards, based on using PEMS for field-testing 
versus using laboratory equipment and instruments for laboratory 
testing?
    (15) Do results of initial field testing trigger any requirement for 
additional field testing or laboratory testing?
    (16) How do I report field-testing results?
    (d) Field testing and this part 1065. Use the following 
specifications for field testing:
    (1) Use the applicability and general provisions of subpart A of 
this part.
    (2) Use equipment specifications in Sec. 1065.101 and in the 
sections from Sec. 1065.140 to the end of subpart B of this part, with 
the exception of Sec. Sec. 1065.140(e)(1) and (4), 1065.170(c)(1)(vi), 
and 1065.195(c). Section 1065.910 identifies additional equipment that 
is specific to field testing.
    (i) For PM samples, configure dilution systems as follows:
    (A) Use good engineering judgment to control dilution air 
temperature. If you choose to directly and actively control dilution air 
temperature, set the temperature to 25  deg.C.
    (B) Control sample temperature to a (32 to 62)  deg.C tolerance, as 
measured anywhere within 20 cm upstream or downstream of the PM storage 
media (such as a filter or oscillating crystal), where the tolerance 
applies only during sampling.
    (C) Maintain filter face velocity to a (5 to 100) cm/s tolerance for 
flow-through media. Compliance with this provision can be verified by 
engineering analysis. This provision does not apply for non-flow-through 
media.
    (ii) For inertial PM balances, there is no requirement to control 
the stabilization environment temperature or dewpoint.

[[Page 251]]

    (3) Use measurement instruments in subpart C of this part, except as 
specified in Sec. 1065.915.
    (4) Use calibrations and verifications in subpart D of this part, 
except as specified in Sec. 1065.920. Section 1065.920 also specifies 
additional calibrations and verifications for field testing.
    (5) Use the provisions of the standard-setting part for selecting 
and maintaining engines in the field instead of the specifications in 
subpart E of this part.
    (6) Use the procedures in Sec. Sec. 1065.930 and 1065.935 to start 
and run a field test. If you use a gravimetric balance for PM, weigh PM 
samples according to Sec. Sec. 1065.590 and 1065.595.
    (7) Use the calculations in subpart G of this part to calculate 
emissions over each test interval. Note that ``test interval'' is 
defined in subpart K of this part 1065, and that the standard setting 
part indicates how to determine test intervals for your engine.
    Section 1065.940 specifies additional calculations for field 
testing. Use any calculations specified in the standard-setting part to 
determine if your engines meet the field-testing standards. The 
standard-setting part may also contain additional calculations that 
determine when further field testing is required.
    (8) Use a typical in-use fuel meeting the specifications of Sec. 
1065.701(d).
    (9) Use the lubricant and coolant specifications in Sec. Sec. 
1065.740 and 1065.745.
    (10) Use the analytical gases and other calibration standards in 
Sec. 1065.750 and Sec. 1065.790.
    (11) If you are testing with oxygenated fuels, use the procedures 
specified for testing with oxygenated fuels in subpart I of this part.
    (12) Apply the definitions and reference materials in subpart K of 
this part.
    (e) Laboratory testing using PEMS. You may use PEMS for testing in a 
laboratory as described in Sec. 1065.901(b). Use the following 
procedures and specifications when using PEMS for laboratory testing:
    (1) Use the applicability and general provisions of subpart A of 
this part.
    (2) Use equipment specifications in subpart B of this part. Section 
1065.910 specifies additional equipment specific to testing with PEMS.
    (3) Use measurement instruments in subpart C of this part, except as 
specified in Sec. 1065.915.
    (4) Use calibrations and verifications in subpart D of this part, 
except as specified in Sec. 1065.920. Section 1065.920 also specifies 
additional calibration and verifications for PEMS.
    (5) Use the provisions of Sec. 1065.401 for selecting engines for 
testing. Use the provisions of subpart E of this part for maintaining 
engines, except as specified in the standard-setting part.
    (6) Use the procedures in subpart F of this part and in the 
standard-setting part to start and run a laboratory test.
    (7) Use the calculations in subpart G of this part to calculate 
emissions over the applicable duty cycle. Section 1065.940 specifies 
additional calculations for testing with PEMS.
    (8) Use a fuel meeting the specifications of subpart H of this part, 
as specified in the standard-setting part.
    (9) Use the lubricant and coolant specifications in Sec. Sec. 
1065.740 and 1065.745.
    (10) Use the analytical gases and other calibration standards in 
Sec. Sec. 1065.750 and 1065.790.
    (11) If you are testing with oxygenated fuels, use the procedures 
specified for testing with oxygenated fuels in subpart I of this part.
    (12) Apply the definitions and reference materials in subpart K of 
this part.
    (f) Summary. The following table summarizes the requirements of 
paragraphs (d) and (e) of this section:

         Table 1 of Sec. 1065.905--Summary of Testing Requirements Specified Outside of This Subpart J
----------------------------------------------------------------------------------------------------------------
                                                                     Applicability for
                                                                   laboratory or similar     Applicability for
              Subpart                  Applicability for field       testing with PEMS     laboratory or similar
                                             testing \1\            without restriction   testing with PEMS with
                                                                            \1\              restrictions \1\
----------------------------------------------------------------------------------------------------------------
A: Applicability and general         Use all....................  Use all...............  Use all.
 provisions.

[[Page 252]]

 
B: Equipment for testing...........  Use Sec. 1065.101 and      Use all...............  Use all. Sec.
                                      Sec. 1065.140 through                              1065.910 specifies
                                      the end of subpart B,                                equipment specific to
                                      except Sec. laboratory testing
                                      1065.140(e)(1) and (4),                              with PEMS.
                                      Sec. 1065.170(c)(1)(vi),
                                      and Sec. 1065.195(c).
                                      Sec. 1065.910 specifies
                                      equipment specific to
                                      field testing.
C: Measurement instruments.........  Use all. Sec. 1065.915     Use all except Sec. Use all except Sec.
                                      allows deviations.           1065.295(c).            1065.295(c). Sec.
                                                                                           1065.915 allows
                                                                                           deviations.
D: Calibrations and verifications..  Use all except Sec. Use all...............  Use all. Sec.
                                      1065.308 and Sec. 1065.920 allows
                                      1065.309. Sec. 1065.920                            deviations, but also
                                      allows deviations, but                               has additional
                                      also has additional                                  specifications.
                                      specifications.
E: Test engine selection,            Do not use. Use standard-    Use all...............  Use all.
 maintenance, and durability.         setting part.
F: Running an emission test in the   Use Sec. Sec. 1065.590    Use all...............  Use all.
 laboratory.                          and 1065.595 for PM Sec.
                                      1065.930 and Sec.
                                      1065.935 to start and run
                                      a field test.
G: Calculations and data             Use all. Sec. 1065.940     Use all...............  Use all. Sec.
 requirements.                        has additional calculation                           1065.940 has
                                      instructions.                                        additional
                                                                                           calculation
                                                                                           instructions.
H: Fuels, engine fluids, analytical  Use all....................  Use all...............  Use all.
 gases, and other calibration
 materials.
I: Testing with oxygenated fuels...  Use all....................  Use all...............  Use all.
K: Definitions and reference         Use all....................  Use all...............  Use all.
 materials.
----------------------------------------------------------------------------------------------------------------
\1\ Refer to paragraphs (d) and (e) of this section for complete specifications.


[70 FR 40516, July 13, 2005, as amended at 73 FR 37344, June 30, 2008; 
75 FR 68465, Nov. 8, 2010; 79 FR 23813, Apr. 28, 2014]



Sec. 1065.910  PEMS auxiliary equipment for field testing.

    For field testing you may use various types of auxiliary equipment 
to attach PEMS to a vehicle or engine and to power PEMS.
    (a) When you use PEMS, you may route engine intake air or exhaust 
through a flow meter. Route the engine intake air or exhaust as follows:
    (1) Flexible connections. Use short flexible connectors where 
necessary.
    (i) You may use flexible connectors to enlarge or reduce the pipe 
diameters to match that of your test equipment.
    (ii) We recommend that you use flexible connectors that do not 
exceed a length of three times their largest inside diameter.
    (iii) We recommend that you use four-ply silicone-fiberglass fabric 
with a temperature rating of at least 315  deg.C for flexible 
connectors. You may use connectors with a spring-steel wire helix for 
support and you may use Nomex \TM\ coverings or linings for durability. 
You may also use any other nonreactive material with equivalent 
permeation-resistance and durability, as long as it seals tightly.
    (iv) Use stainless-steel hose clamps to seal flexible connectors, or 
use clamps that seal equivalently.
    (v) You may use additional flexible connectors to connect to flow 
meters.
    (2) Tubing. Use rigid 300 series stainless steel tubing to connect 
between flexible connectors. Tubing may be straight or bent to 
accommodate vehicle geometry. You may use ``T'' or ``Y'' fittings made 
of 300 series stainless steel tubing to join multiple connections, or 
you may cap or plug redundant flow paths if the engine manufacturer 
recommends it.

[[Page 253]]

    (3) Flow restriction. Use flow meters, connectors, and tubing that 
do not increase flow restriction so much that it exceeds the 
manufacturer's maximum specified value. You may verify this at the 
maximum exhaust flow rate by measuring pressure at the manufacturer-
specified location with your system connected. You may also perform an 
engineering analysis to verify an acceptable configuration, taking into 
account the maximum exhaust flow rate expected, the field test system's 
flexible connectors, and the tubing's characteristics for pressure drops 
versus flow.
    (b) For vehicles or other motive equipment, we recommend installing 
PEMS in the same location where a passenger might sit. Follow PEMS 
manufacturer instructions for installing PEMS in cargo spaces, engine 
spaces, or externally such that PEMS is directly exposed to the outside 
environment. We recommend locating PEMS where it will be subject to 
minimal sources of the following parameters:
    (1) Ambient temperature changes.
    (2) Ambient pressure changes.
    (3) Electromagnetic radiation.
    (4) Mechanical shock and vibration.
    (5) Ambient hydrocarbons--if using a FID analyzer that uses ambient 
air as FID burner air.
    (c) Use mounting hardware as required for securing flexible 
connectors, ambient sensors, and other equipment. Use structurally sound 
mounting points such as vehicle frames, trailer hitch receivers, walk 
spaces, and payload tie-down fittings. We recommend mounting hardware 
such as clamps, suction cups, and magnets that are specifically designed 
for your application. We also recommend considering mounting hardware 
such as commercially available bicycle racks, trailer hitches, and 
luggage racks where applicable.
    (d) Field testing may require portable electrical power to run your 
test equipment. Power your equipment, as follows:
    (1) You may use electrical power from the vehicle, equipment, or 
vessel, up to the highest power level, such that all the following are 
true:
    (i) The power system is capable of safely supplying power, such that 
the power demand for testing does not overload the power system.
    (ii) The engine emissions do not change significantly as a result of 
the power demand for testing.
    (iii) The power demand for testing does not increase output from the 
engine by more than 1% of its maximum power.
    (2) You may install your own portable power supply. For example, you 
may use batteries, fuel cells, a portable generator, or any other power 
supply to supplement or replace your use of vehicle power. You may 
connect an external power source directly to the vehicle's, vessel's, or 
equipment's power system; however, during a test interval (such as an 
NTE event) you must not supply power to the vehicle's power system in 
excess of 1% of the engine's maximum power.

[73 FR 37344, June 30, 2008, as amended at 75 FR 23058, Apr. 30, 2010]



Sec. 1065.915  PEMS instruments.

    (a) Instrument specifications. We recommend that you use PEMS that 
meet the specifications of subpart C of this part. For unrestricted use 
of PEMS in a laboratory or similar environment, use a PEMS that meets 
the same specifications as each lab instrument it replaces. For field 
testing or for testing with PEMS in a laboratory or similar environment, 
under the provisions of Sec. 1065.905(b), the specifications in the 
following table apply instead of the specifications in Table 1 of Sec. 
1065.205.

                                 Table 1 of Sec. 1065.915--Recommended Minimum PEMS Measurement Instrument Performance
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                          Rise time,
                                     Measured quantity   t10	90, and    Recording update
           Measurement                    symbol          fall time,       frequency           Accuracy \1\      Repeatability \1\        Noise \1\
                                                            t90	10
--------------------------------------------------------------------------------------------------------------------------------------------------------
Engine speed transducer..........  fn..................          1 s  1 Hz means.........  5% of pt. or 1% of   2% of pt. or 1% of   0.5% of max.
                                                                                            max.                 max.

[[Page 254]]

 
Engine torque estimator, BSFC      T or BSFC...........          1 s  1 Hz means.........  8% of pt. or 5% of   2% of pt. or 1% of   1% of max.
 (This is a signal from an                                                                  max.                 max.
 engine's ECM).
General pressure transducer (not   p...................          5 s  1 Hz...............  5% of pt. or 5% of   2% of pt. or 0.5%    1% of max.
 a part of another instrument).                                                             max.                 of max.
Atmospheric pressure meter.......  patmos..............         50 s  0.1 Hz.............  250 Pa.............  200 Pa.............  100 Pa.
General temperature sensor (not a  T...................          5 s  1 Hz...............  1% of pt. K or 5 K.  0.5% of pt. K or 2   0.5% of max 0.5 K.
 part of another instrument).                                                                                    K.
General dewpoint sensor..........  Tdew................         50 s  0.1 Hz.............  3 K................  1 K................  1 K.
Exhaust flow meter...............  n...................          1 s  1 Hz means.........  5% of pt. or 3% of   2% of pt...........  2% of max.
                                                                                            max.
Dilution air, inlet air, exhaust,  n...................          1 s  1 Hz means.........  2.5% of pt. or 1.5%  1.25% of pt. or      1% of max.
 and sample flow meters.                                                                    of max.              0.75% of max.
Continuous gas analyzer..........  x...................          5 s  1 Hz...............  4% of pt. or 4% of   2% of pt. or 2% of   1% of max.
                                                                                            meas.                meas.
Gravimetric PM balance...........  mPM.................  ...........  ...................  See Sec. 1065.790  0.5 [micro] g......
Inertial PM balance..............  mPM.................  ...........  ...................  4% of pt. or 4% of   2% of pt. or 2% of   1% of max.
                                                                                            meas.                meas.
--------------------------------------------------------------------------------------------------------------------------------------------------------
\1\ Accuracy, repeatability, and noise are all determined with the same collected data, as described in Sec. 1065.305, and based on absolute values.
  ``pt.'' refers to the overall flow-weighted mean value expected at the standard; ``max.'' refers to the peak value expected at the standard over any
  test interval, not the maximum of the instrument's range; ``meas'' refers to the actual flow-weighted mean measured over any test interval.

    (b) Redundant measurements. For all PEMS described in this subpart, 
you may use data from multiple instruments to calculate test results for 
a single test. If you use redundant systems, use good engineering 
judgment to use multiple measured values in calculations or to disregard 
individual measurements. Note that you must keep your results from all 
measurements, as described in Sec. 1065.25. This requirement applies 
whether or not you actually use the measurements in your calculations.
    (c) Field-testing ambient effects on PEMS. We recommend that you use 
PEMS that are only minimally affected by ambient conditions such as 
temperature, pressure, humidity, physical orientation, mechanical shock 
and vibration, electromagnetic radiation, and ambient hydrocarbons. 
Follow the PEMS manufacturer's instructions for proper installation to 
isolate PEMS from ambient conditions that affect their performance. If a 
PEMS is inherently affected by ambient conditions that you cannot 
control, you may monitor those conditions and adjust the PEMS signals to 
compensate for the ambient effect. The standard-setting part may also 
specify the use of one or more field-testing adjustments or measurement 
allowances that you apply to results or standards to account for ambient 
effects on PEMS.
    (d) ECM signals. You may use signals from the engine's electronic 
control module (ECM) in place of values measured by individual 
instruments within a PEMS, subject to the following provisions:
    (1) Recording ECM signals. If your ECM updates a broadcast signal 
more or less frequently than 1 Hz, process data as follows:
    (i) If your ECM updates a broadcast signal more frequently than 1 
Hz, use PEMS to sample and record the signal's value more frequently. 
Calculate and record the 1 Hz mean of the more frequently updated data.
    (ii) If your ECM updates a broadcast signal less frequently than 1 
Hz, use PEMS to sample and record the signal's value at the most 
frequent rate. Linearly interpolate between recorded

[[Page 255]]

values and record the interpolated values at 1 Hz.
    (iii) Optionally, you may use PEMS to electronically filter the ECM 
signals to meet the rise time and fall time specifications in Table 1 of 
this section. Record the filtered signal at 1 Hz.
    (2) Omitting ECM signals. Replace any discontinuous or irrational 
ECM data with linearly interpolated values from adjacent data.
    (3) Aligning ECM signals with other data. You must perform time-
alignment and dispersion of ECM signals, according to PEMS manufacturer 
instructions and using good engineering judgment.
    (4) ECM signals for determining test intervals. You may use any 
combination of ECM signals, with or without other measurements, to 
determine the start-time and end-time of a test interval.
    (5) ECM signals for determining brake-specific emissions. You may 
use any combination of ECM signals, with or without other measurements, 
to estimate engine speed, torque, brake-specific fuel consumption (BSFC, 
in units of mass of fuel per kW-hr), and fuel rate for use in brake-
specific emission calculations. We recommend that the overall 
performance of any speed, torque, or BSFC estimator should meet the 
performance specifications in Table 1 of this section. We recommend 
using one of the following methods:
    (i) Speed. Use the engine speed signal directly from the ECM. This 
signal is generally accurate and precise. You may develop your own speed 
algorithm based on other ECM signals.
    (ii) Torque. Use one of the following:
    (A) ECM torque. Use the engine-torque signal directly from the ECM, 
if broadcast. Determine if this signal is proportional to indicated 
torque or brake torque. If it is proportional to indicated torque, 
subtract friction torque from indicated torque and record the result as 
brake torque. Friction torque may be a separate signal broadcast from 
the ECM or you may have to determine it from laboratory data as a 
function of engine speed.
    (B) ECM %-load. Use the %-load signal directly from the ECM, if 
broadcast. Determine if this signal is proportional to indicated torque 
or brake torque. If it is proportional to indicated torque, subtract the 
minimum %-load value from the %-load signal. Multiply this result by the 
maximum brake torque at the corresponding engine speed. Maximum brake 
torque versus speed information is commonly published by the engine 
manufacturer.
    (C) Your algorithms. You may develop and use your own combination of 
ECM signals to determine torque.
    (iii) BSFC. Use one of the following:
    (A) Use ECM engine speed and ECM fuel flow signals to interpolate 
brake-specific fuel consumption data, which might be available from an 
engine laboratory as a function of ECM engine speed and ECM fuel 
signals.
    (B) Use a single BSFC value that approximates the BSFC value over a 
test interval (as defined in subpart K of this part). This value may be 
a nominal BSFC value for all engine operation determined over one or 
more laboratory duty cycles, or it may be any other BSFC that you 
determine. If you use a nominal BSFC, we recommend that you select a 
value based on the BSFC measured over laboratory duty cycles that best 
represent the range of engine operation that defines a test interval for 
field-testing. You may use the methods of this paragraph (d)(5)(iii)(B) 
only if it does not adversely affect your ability to demonstrate 
compliance with applicable standards.
    (C) You may develop and use your own combination of ECM signals to 
determine BSFC.
    (iv) ECM fuel rate. Use the fuel rate signal directly from the ECM 
and chemical balance to determine the molar flow rate of exhaust. Use 
Sec. 1065.655(d) to determine the carbon mass fraction of fuel. You may 
alternatively develop and use your own combination of ECM signals to 
determine fuel mass flow rate.
    (v) Other ECM signals. You may ask to use other ECM signals for 
determining brake-specific emissions, such as ECM air flow. We must 
approve the use of such signals in advance.
    (6) Permissible deviations. ECM signals may deviate from the 
specifications of this part 1065, but the expected deviation must not 
prevent you from demonstrating that you meet the applicable standards. 
For example, your emission results may be sufficiently below

[[Page 256]]

an applicable standard, such that the deviation would not significantly 
change the result. As another example, a very low engine-coolant 
temperature may define a logical statement that determines when a test 
interval may start. In this case, even if the ECM's sensor for detecting 
coolant temperature was not very accurate or repeatable, its output 
would never deviate so far as to significantly affect when a test 
interval may start.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37344, June 30, 2008; 
73 FR 59342, Oct. 8, 2008; 75 FR 68466, Nov. 8, 2010; 76 FR 57467, Sept. 
15, 2011; 79 FR 23813, Apr. 28, 2014]



Sec. 1065.920  PEMS calibrations and verifications.

    (a) Subsystem calibrations and verifications. Use all the applicable 
calibrations and verifications in subpart D of this part, including the 
linearity verifications in Sec. 1065.307, to calibrate and verify PEMS. 
Note that a PEMS does not have to meet the system-response and updating-
recording verifications of Sec. 1065.308 and Sec. 1065.309 if it meets 
the overall verification described in paragraph (b) of this section or 
if it measures PM using any method other than that described in Sec. 
1065.170(c)(1). This section does not apply to ECM signals. Note that 
because the regulations of this part require you to use good engineering 
judgment, it may be necessary to perform additional verifications and 
analysis. It may also be necessary to limit the range of conditions 
under which the PEMS can be used or to include specific additional 
maintenance to ensure that it functions properly under the test 
conditions. As provided in 40 CFR 1068.5, we will deem your system to 
not meet the requirements of this section if we determine that you did 
not use good engineering judgment to verify the measurement equipment. 
We may also deem your system to meet these requirements only under 
certain test conditions. If we ask for it, you must send us a summary of 
your verifications. We may also ask you to provide additional 
information or analysis to support your conclusions.
    (b) Overall verification. This paragraph (b) specifies methods and 
criteria for verifying the overall performance of systems not fully 
compliant with requirements that apply for laboratory testing. Maintain 
records to show that the particular make, model, and configuration of 
your PEMS meets this verification. You may rely on data and other 
information from the PEMS manufacturer. However, we recommend that you 
generate your own records to show that your specific PEMS meets this 
verification. If you upgrade or change the configuration of your PEMS, 
your record must show that your new configuration meets this 
verification. The verification required by this section consists of 
operating an engine over a duty cycle in the laboratory and 
statistically comparing data generated and recorded by the PEMS with 
data simultaneously generated and recorded by laboratory equipment as 
follows:
    (1) Mount an engine on a dynamometer for laboratory testing. Prepare 
the laboratory and PEMS for emission testing, as described in this part, 
to get simultaneous measurements. We recommend selecting an engine with 
emission levels close to the applicable duty-cycle standards, if 
possible.
    (2) Select or create a duty cycle that has all the following 
characteristics:
    (i) Engine operation that represents normal in-use speeds, loads, 
and degree of transient activity. Consider using data from previous 
field tests to generate a cycle.
    (ii) A duration of (20 to 40) min.
    (iii) At least 50% of engine operating time must include at least 10 
valid test intervals for calculating emission levels for field testing. 
For example, for highway compression-ignition engines, select a duty 
cycle in which at least 50% of the engine operating time can be used to 
calculate valid NTE events.
    (3) Starting with a warmed-up engine, run a valid emission test with 
the duty cycle from paragraph (b)(2) of this section. The laboratory and 
PEMS must both meet applicable validation requirements, such as drift 
validation, hydrocarbon contamination validation, and proportional 
validation.
    (4) Determine the brake-specific emissions for each test interval 
for both laboratory and the PEMS measurements, as follows:

[[Page 257]]

    (i) For both laboratory and PEMS measurements, use identical values 
to determine the beginning and end of each test interval.
    (ii) For both laboratory and PEMS measurements, use identical values 
to determine total work over each test interval.
    (iii) If the standard-setting part specifies the use of a 
measurement allowance for field testing, also apply the measurement 
allowance during calibration using good engineering judgment. If the 
measurement allowance is normally added to the standard, this means you 
must subtract the measurement allowance from the measured PEMS brake-
specific emission result.
    (iv) Round results to the same number of significant digits as the 
standard.
    (5) Repeat the engine duty cycle and calculations until you have at 
least 100 valid test intervals.
    (6) For each test interval and emission, subtract the lab result 
from the PEMS result.
    (7) The PEMS passes the verification of this paragraph (b) if any 
one of the following are true for each constituent:
    (i) 91% or more of the differences are zero or less than zero.
    (ii) The entire set of test-interval results passes the 95% 
confidence alternate-procedure statistics for field testing (t-test and 
F-test) specified in subpart A of this part.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37345, June 30, 2008; 
75 FR 68467, Nov. 8, 2010; 79 FR 23814, Apr. 28, 2014]



Sec. 1065.925  PEMS preparation for field testing.

    Take the following steps to prepare PEMS for field testing:
    (a) Verify that ambient conditions at the start of the test are 
within the limits specified in the standard-setting part. Continue to 
monitor these values to determine if ambient conditions exceed the 
limits during the test.
    (b) Install a PEMS and any accessories needed to conduct a field 
test.
    (c) Power the PEMS and allow pressures, temperatures, and flows to 
stabilize to their operating set points.
    (d) Bypass or purge any gaseous sampling PEMS instruments with 
ambient air until sampling begins to prevent system contamination from 
excessive cold-start emissions.
    (e) Conduct calibrations and verifications.
    (f) Operate any PEMS dilution systems at their expected flow rates 
using a bypass.
    (g) If you use a gravimetric balance to determine whether an engine 
meets an applicable PM standard, follow the procedures for PM sample 
preconditioning and tare weighing as described in Sec. 1065.590. 
Operate the PM-sampling system at its expected flow rates using a 
bypass.
    (h) Verify the amount of contamination in the PEMS HC sampling 
system before the start of the field test as follows:
    (1) Select the HC analyzer range for measuring the maximum 
concentration expected at the HC standard.
    (2) Zero the HC analyzers using a zero gas or ambient air introduced 
at the analyzer port. When zeroing a FID, use the FID's burner air that 
would be used for in-use measurements (generally either ambient air or a 
portable source of burner air).
    (3) Span the HC analyzer using span gas introduced at the analyzer 
port.
    (4) Overflow zero or ambient air at the HC probe inlet or into a tee 
near the probe outlet.
    (5) Measure the HC concentration in the sampling system:
    (i) For continuous sampling, record the mean HC concentration as 
overflow zero air flows.
    (ii) For batch sampling, fill the sample medium and record its mean 
concentration.
    (6) Record this value as the initial HC concentration, 
xTHCinit, and use it to correct measured values as described 
in Sec. 1065.660.
    (7) If the initial HC concentration exceeds the greater of the 
following values, determine the source of the contamination and take 
corrective action, such as purging the system or replacing contaminated 
portions:
    (i) 2% of the flow-weighted mean concentration expected at the 
standard or measured during testing.
    (ii) 2 [micro] mol/mol.
    (8) If corrective action does not resolve the deficiency, you may 
use a contaminated HC system if it does not

[[Page 258]]

prevent you from demonstrating compliance with the applicable emission 
standards.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37345, June 30, 2008; 
73 FR 59342, Oct. 8, 2008; 75 FR 68467, Nov. 8, 2010; 76 FR 57467, Sept. 
15, 2011]



Sec. 1065.930  Engine starting, restarting, and shutdown.

    Unless the standard-setting part specifies otherwise, start, 
restart, and shut down the test engine for field testing as follows:
    (a) Start or restart the engine as described in the owners manual.
    (b) If the engine does not start after 15 seconds of cranking, stop 
cranking and determine the reason it failed to start. However, you may 
crank the engine longer than 15 seconds, as long as the owners manual or 
the service-repair manual describes the longer cranking time as normal.
    (c) Respond to engine stalling with the following steps:
    (1) If the engine stalls during a required warm-up before emission 
sampling begins, restart the engine and continue warm-up.
    (2) If the engine stalls at any other time after emission sampling 
begins, restart the engine and continue testing.
    (d) Shut down and restart the engine according to the manufacturer's 
specifications, as needed during normal operation in-use, but continue 
emission sampling until the field test is complete.



Sec. 1065.935  Emission test sequence for field testing.

    (a) Time the start of field testing as follows:
    (1) If the standard-setting part requires only hot-stabilized 
emission measurements, operate the engine in-use until the engine 
coolant, block, or head absolute temperature is within [10% of its mean 
value for the previous 2 min or until an engine thermostat controls 
engine temperature with coolant or air flow.
    (2) If the standard-setting part requires hot-start emission 
measurements, shut down the engine after at least 2 min at the 
temperature tolerance specified in paragraph (a)(1) of this section. 
Start the field test within 20 min of engine shutdown.
    (3) If the standard-setting part requires cold-start emission 
measurements, proceed to the steps specified in paragraph (b) of this 
section.
    (b) Take the following steps before emission sampling begins:
    (1) For batch sampling, connect clean storage media, such as 
evacuated bags or tare-weighed PM sample media.
    (2) Operate the PEMS according to the instrument manufacturer's 
instructions and using good engineering judgment.
    (3) Operate PEMS heaters, dilution systems, sample pumps, cooling 
fans, and the data-collection system.
    (4) Pre-heat or pre-cool PEMS heat exchangers in the sampling system 
to within their tolerances for operating temperatures.
    (5) Allow all other PEMS components such as sample lines, filters, 
and pumps to stabilize at operating temperature.
    (6) Verify that no significant vacuum-side leak exists in the PEMS, 
as described in Sec. 1065.345.
    (7) Adjust PEMS flow rates to desired levels, using bypass flow if 
applicable.
    (8) Zero and span all PEMS gas analyzers using NIST-traceable gases 
that meet the specifications of Sec. 1065.750.
    (c) Start testing as follows:
    (1) Before the start of the first test interval, zero or re-zero any 
PEMS electronic integrating devices, as needed.
    (2) If the engine is already running and warmed up and starting is 
not part of field testing, start the field test by simultaneously 
starting to sample exhaust, record engine and ambient data, and 
integrate measured values using a PEMS.
    (3) If engine starting is part of field testing, start field testing 
by simultaneously starting to sample from the exhaust system, record 
engine and ambient data, and integrate measured values using a PEMS. 
Then start the engine.
    (d) Continue the test as follows:
    (1) Continue to sample exhaust, record data and integrate measured 
values throughout normal in-use operation of the engine.
    (2) Between each test interval, zero or re-zero any electronic 
integrating

[[Page 259]]

devices, and reset batch storage media, as needed.
    (3) The engine may be stopped and started, but continue to sample 
emissions throughout the entire field test.
    (4) Conduct periodic verifications such as zero and span 
verifications on PEMS gas analyzers, as recommended by the PEMS 
manufacturer or as indicated by good engineering judgment. Results from 
these verifications will be used to calculate and correct for drift 
according to paragraph (g) of this section. Do not include data recorded 
during verifications in emission calculations.
    (5) You may periodically condition and analyze batch samples in-
situ, including PM samples; for example you may condition an inertial PM 
balance substrate if you use an inertial balance to measure PM.
    (6) You may have personnel monitoring and adjusting the PEMS during 
a test, or you may operate the PEMS unattended.
    (e) Stop testing as follows:
    (1) Continue sampling as needed to get an appropriate amount of 
emission measurement, according to the standard setting part. If the 
standard-setting part does not describe when to stop sampling, develop a 
written protocol before you start testing to establish how you will stop 
sampling. You may not determine when to stop testing based on emission 
results.
    (2) At the end of the field test, allow the sampling systems' 
response times to elapse and then stop sampling. Stop any integrators 
and indicate the end of the test cycle on the data-collection medium.
    (3) You may shut down the engine before or after you stop sampling.
    (f) For any proportional batch sample, such as a bag sample or PM 
sample, verify for each test interval whether or not proportional 
sampling was maintained according to Sec. 1065.545. Void the sample for 
any test interval that did not maintain proportional sampling according 
to Sec. 1065.545.
    (g) Take the following steps after emission sampling is complete:
    (1) As soon as practical after the emission sampling, analyze any 
gaseous batch samples.
    (2) If you used dilution air, either analyze background samples or 
assume that background emissions were zero. Refer to Sec. 1065.140 for 
dilution-air specifications.
    (3) After quantifying all exhaust gases, record mean analyzer values 
after stabilizing a zero gas to each analyzer, then record mean analyzer 
values after stabilizing the span gas to the analyzer. Stabilization may 
include time to purge an analyzer of any sample gas, plus any additional 
time to account for analyzer response. Use these recorded values to 
correct for drift as described in Sec. 1065.550.
    (4) Invalidate any test intervals that do not meet the range 
criteria in Sec. 1065.550. Note that it is acceptable that analyzers 
exceed 100% of their ranges when measuring emissions between test 
intervals, but not during test intervals. You do not have to retest an 
engine in the field if the range criteria are not met.
    (5) Invalidate any test intervals that do not meet the drift 
criterion in Sec. 1065.550. For NMHC, invalidate any test intervals if 
the difference between the uncorrected and the corrected brake-specific 
NMHC emission values are within [10% of the uncorrected results or the 
applicable standard, whichever is greater. For test intervals that do 
meet the drift criterion, correct those test intervals for drift 
according to Sec. 1065.672 and use the drift corrected results in 
emissions calculations.
    (6) Unless you weighed PM in-situ, such as by using an inertial PM 
balance, place any used PM samples into covered or sealed containers and 
return them to the PM-stabilization environment and weigh them as 
described in Sec. 1065.595.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37345, June 30, 2008]



Sec. 1065.940  Emission calculations.

    (a) Perform emission calculations as described in Sec. 1065.650 to 
calculate brake-specific emissions for each test interval using any 
applicable information and instructions in the standard-setting part.
    (b) You may use a fixed molar mass for the diluted exhaust mixture 
for

[[Page 260]]

field testing. Determine this fixed value by engineering analysis.

[75 FR 68467, Nov. 8, 2010]



          Subpart K_Definitions and Other Reference Information



Sec. 1065.1001  Definitions.

    The definitions in this section apply to this part. The definitions 
apply to all subparts unless we note otherwise. All undefined terms have 
the meaning the Act gives them. The definitions follow:
    300 series stainless steel means any stainless steel alloy with a 
Unified Numbering System for Metals and Alloys number designated from 
S30100 to S39000. For all instances in this part where we specify 300 
series stainless steel, such parts must also have a smooth inner-wall 
construction. We recommend an average roughness, Ra, no 
greater than 4 [micro] m.
    Accuracy means the absolute difference between a reference quantity 
and the arithmetic mean of ten mean measurements of that quantity. 
Determine instrument accuracy, repeatability, and noise from the same 
data set. We specify a procedure for determining accuracy in Sec. 
1065.305.
    Act means the Clean Air Act, as amended, 42 U.S.C. 7401-7671q.
    Adjustable parameter means any device, system, or element of design 
that someone can adjust (including those which are difficult to access) 
and that, if adjusted, may affect emissions or engine performance during 
emission testing or normal in-use operation. This includes, but is not 
limited to, parameters related to injection timing and fueling rate. In 
some cases, this may exclude a parameter that is difficult to access if 
it cannot be adjusted to affect emissions without significantly 
degrading engine performance, or if it will not be adjusted in a way 
that affects emissions during in-use operation.
    Aerodynamic diameter means the diameter of a spherical water droplet 
that settles at the same constant velocity as the particle being 
sampled.
    Aftertreatment means relating to a catalytic converter, particulate 
filter, or any other system, component, or technology mounted downstream 
of the exhaust valve (or exhaust port) whose design function is to 
decrease emissions in the engine exhaust before it is exhausted to the 
environment. Exhaust-gas recirculation (EGR) and turbochargers are not 
aftertreatment.
    Allowed procedures means procedures that we either specify in this 
part 1065 or in the standard-setting part or approve under Sec. 
1065.10.
    Alternate procedures means procedures allowed under Sec. 
1065.10(c)(7).
    Applicable standard means an emission standard to which an engine is 
subject; or a family emission limit to which an engine is certified 
under an emission credit program in the standard-setting part.
    Aqueous condensation means the precipitation of water-containing 
constituents from a gas phase to a liquid phase. Aqueous condensation is 
a function of humidity, pressure, temperature, and concentrations of 
other constituents such as sulfuric acid. These parameters vary as a 
function of engine intake-air humidity, dilution-air humidity, engine 
air-to-fuel ratio, and fuel composition--including the amount of 
hydrogen and sulfur in the fuel.
    Atmospheric pressure means the wet, absolute, atmospheric static 
pressure. Note that if you measure atmospheric pressure in a duct, you 
must ensure that there are negligible pressure losses between the 
atmosphere and your measurement location, and you must account for 
changes in the duct's static pressure resulting from the flow.
    Auto-ranging means a gas analyzer function that automatically 
changes the analyzer digital resolution to a larger range of 
concentrations as the concentration approaches 100% of the analyzer's 
current range. Auto-ranging does not mean changing an analog amplifier 
gain within an analyzer.
    Auxiliary emission-control device means any element of design that 
senses temperature, motive speed, engine RPM, transmission gear, or any 
other parameter for the purpose of activating, modulating, delaying, or 
deactivating the operation of any part of the emission-control system.
    Average means the arithmetic mean of a sample.

[[Page 261]]

    Brake power has the meaning given in the standard-setting part. If 
it is not defined in the standard-setting part, brake power means the 
usable power output of the engine, not including power required to fuel, 
lubricate, or heat the engine, circulate coolant to the engine, or to 
operate aftertreatment devices. If the engine does not power these 
accessories during a test, subtract the work required to perform these 
functions from the total work used in brake-specific emission 
calculations. Subtract engine fan work from total work only for air-
cooled engines.
    C1-equivalent means a convention of expressing HC concentrations 
based on the total number of carbon atoms present, such that the 
C1-equivalent of a molar HC concentration equals the molar 
concentration multiplied by the mean number of carbon atoms in each HC 
molecule. For example, the C1-equivalent of 10 [micro] mol/
mol of propane (C3H8) is 30 [micro] mol/mol. 
C1-equivalent molar values may be denoted as ``ppmC'' in the 
standard-setting part. Molar mass may also be expressed on a 
C1 basis. Note that calculating HC masses from molar 
concentrations and molar masses is only valid where they are each 
expressed on the same carbon basis.
    Calibration means the process of setting a measurement system's 
response so that its output agrees with a range of reference signals. 
Contrast with ``verification''.
    Calibration gas means a purified gas mixture used to calibrate gas 
analyzers. Calibration gases must meet the specifications of Sec. 
1065.750. Note that calibration gases and span gases are qualitatively 
the same, but differ in terms of their primary function. Various 
performance verification checks for gas analyzers and sample handling 
components might refer to either calibration gases or span gases.
    Certification means relating to the process of obtaining a 
certificate of conformity for an engine family that complies with the 
emission standards and requirements in the standard-setting part.
    Compression-ignition means relating to a type of reciprocating, 
internal-combustion engine that is not a spark-ignition engine.
    Confidence interval means the range associated with a probability 
that a quantity will be considered statistically equivalent to a 
reference quantity.
    Constant-speed engine means an engine whose certification is limited 
to constant-speed operation. Engines whose constant-speed governor 
function is removed or disabled are no longer constant-speed engines.
    Constant-speed operation means engine operation with a governor that 
automatically controls the operator demand to maintain engine speed, 
even under changing load. Governors do not always maintain speed exactly 
constant. Typically speed can decrease (0.1 to 10) % below the speed at 
zero load, such that the minimum speed occurs near the engine's point of 
maximum power. (Note: An engine with an adjustable governor setting may 
be considered to operate at constant speed, subject to our approval. For 
such engines, the governor setting is considered an adjustable 
parameter.)
    Coriolis meter means a flow-measurement instrument that determines 
the mass flow of a fluid by sensing the vibration and twist of specially 
designed flow tubes as the flow passes through them. The twisting 
characteristic is called the Coriolis effect. According to Newton's 
Second Law of Motion, the amount of sensor tube twist is directly 
proportional to the mass flow rate of the fluid flowing through the 
tube. See Sec. 1065.220.
    Designated Compliance Officer means the Director, Compliance and 
Innovative Strategies Division (6405-J), U.S. Environmental Protection 
Agency, 1200 Pennsylvania Ave., NW., Washington, DC 20460.
    Dewpoint means a measure of humidity stated as the equilibrium 
temperature at which water condenses under a given pressure from moist 
air with a given absolute humidity. Dewpoint is specified as a 
temperature in  deg.C or K, and is valid only for the pressure at which 
it is measured. See Sec. 1065.645 to determine water vapor mole 
fractions from dewpoints using the pressure at which the dewpoint is 
measured.

[[Page 262]]

    Diesel exhaust fluid (DEF) means a liquid reducing agent (other than 
the engine fuel) used in conjunction with selective catalytic reduction 
to reduce NOX emissions. Diesel exhaust fluid is generally 
understood to be an aqueous solution of urea conforming to the 
specifications of ISO 18611 or ISO 22241.
    Dilution ratio (DR) means the amount of diluted exhaust per amount 
of undiluted exhaust.
    Discrete-mode means relating to a discrete-mode type of steady-state 
test, as described in the standard-setting part.
    Dispersion means either:
    (1) The broadening and lowering of a signal due to any fluid 
capacitance, fluid mixing, or electronic filtering in a sampling system. 
(Note: To adjust a signal so its dispersion matches that of another 
signal, you may adjust the system's fluid capacitance, fluid mixing, or 
electronic filtering.)
    (2) The mixing of a fluid, especially as a result of fluid 
mechanical forces or chemical diffusion.
    Drift means the difference between a zero or calibration signal and 
the respective value reported by a measurement instrument immediately 
after it was used in an emission test, as long as you zeroed and spanned 
the instrument just before the test.
    Duty cycle means one of the following:
    (1) A series of speed and torque values (or power values) that an 
engine must follow during a laboratory test. Duty cycles are specified 
in the standard-setting part. A single duty cycle may consist of one or 
more test intervals. A series of speed and torque values meeting the 
definition of this paragraph (1) may also be considered a test cycle. 
For example, a duty cycle may be a ramped-modal cycle, which has one 
test interval; a cold-start plus hot-start transient cycle, which has 
two test intervals; or a discrete-mode cycle, which has one test 
interval for each mode.
    (2) A set of weighting factors and the corresponding speed and 
torque values, where the weighting factors are used to combine the 
results of multiple test intervals into a composite result.
    Electric power generation application means an application whose 
purpose is to generate a precise frequency of electricity, which is 
characterized by an engine that controls engine speed very precisely. 
This would generally not apply to welders or portable home generators.
    Electronic control module means an engine's electronic device that 
uses data from engine sensors to control engine parameters.
    Emission-control system means any device, system, or element of 
design that controls or reduces the emissions of regulated pollutants 
from an engine.
    Emission-data engine means an engine that is tested for 
certification. This includes engines tested to establish deterioration 
factors.
    Emission-related maintenance means maintenance that substantially 
affects emissions or is likely to substantially affect emission 
deterioration.
    Engine family means a group of engines with similar emission 
characteristics throughout the useful life, as specified in the 
standard-setting part.
    Engine governed speed means the engine operating speed when it is 
controlled by the installed governor.
    Exhaust-gas recirculation means a technology that reduces emissions 
by routing exhaust gases that had been exhausted from the combustion 
chamber(s) back into the engine to be mixed with incoming air before or 
during combustion. The use of valve timing to increase the amount of 
residual exhaust gas in the combustion chamber(s) that is mixed with 
incoming air before or during combustion is not considered exhaust-gas 
recirculation for the purposes of this part.
    Fall time, t90-10, means the time interval of a 
measurement instrument's response after any step decrease to the input 
between the following points:
    (1) The point at which the response has fallen 10% of the total 
amount it will fall in response to the step change.
    (2) The point at which the response has fallen 90% of the total 
amount it will fall in response to the step change.
    Flow-weighted mean means the mean of a quantity after it is weighted 
proportional to a corresponding flow rate. For example, if a gas 
concentration is measured continuously from the raw exhaust of an 
engine, its flow-weighted mean concentration is the sum of the

[[Page 263]]

products of each recorded concentration times its respective exhaust 
flow rate, divided by the sum of the recorded flow rates. As another 
example, the bag concentration from a CVS system is the same as the 
flow-weighted mean concentration, because the CVS system itself flow-
weights the bag concentration.
    Fuel type means a general category of fuels such as gasoline or LPG. 
There can be multiple grades within a single type of fuel, such as all-
season and winter-grade gasoline.
    Good engineering judgment means judgments made consistent with 
generally accepted scientific and engineering principles and all 
available relevant information. See 40 CFR 1068.5 for the administrative 
process we use to evaluate good engineering judgment.
    HEPA filter means high-efficiency particulate air filters that are 
rated to achieve a minimum initial particle-removal efficiency of 99.97% 
using ASTM F1471 (incorporated by reference in Sec. 1065.1010).
    High-idle speed means the engine speed at which an engine governor 
function controls engine speed with operator demand at maximum and with 
zero load applied. ``Warm high-idle speed'' is the high-idle speed of a 
warmed-up engine.
    High-speed governor means any device, system, or element of design 
that modulates the engine output torque for the purpose of limiting the 
maximum engine speed.
    Hydraulic diameter means the diameter of a circle whose area is 
equal to the area of a noncircular cross section of tubing, including 
its wall thickness. The wall thickness is included only for the purpose 
of facilitating a simplified and nonintrusive measurement.
    Hydrocarbon (HC) means THC, THCE, NMHC, NMNEHC, NMOG, or NMHCE, as 
applicable. Hydrocarbon generally means the hydrocarbon group on which 
the emission standards are based for each type of fuel and engine.
    Identification number means a unique specification (for example, a 
model number/serial number combination) that allows someone to 
distinguish a particular engine from other similar engines.
    Idle speed means the engine speed at which an engine governor 
function controls engine speed with operator demand at minimum and with 
minimum load applied (greater than or equal to zero). For engines 
without a governor function that controls idle speed, idle speed means 
the manufacturer-declared value for lowest engine speed possible with 
minimum load. This definition does not apply for operation designated as 
``high-idle speed.'' ``Warm idle speed'' is the idle speed of a warmed-
up engine.
    Intermediate test speed has the meaning given in Sec. 1065.610.
    Linearity means the degree to which measured values agree with 
respective reference values. Linearity is quantified using a linear 
regression of pairs of measured values and reference values over a range 
of values expected or observed during testing. Perfect linearity would 
result in an intercept, a0, equal to zero, a slope, 
a1, of one, a coefficient of determination, r\2\, of one, and 
a standard error of the estimate, SEE, of zero. The term ``linearity'' 
is not used in this part to refer to the shape of a measurement 
instrument's unprocessed response curve, such as a curve relating 
emission concentration to voltage output. A properly performing 
instrument with a nonlinear response curve will meet linearity 
specifications.
    Manufacturer has the meaning given in section 216(1) of the Act. In 
general, this term includes any person who manufactures an engine or 
vehicle for sale in the United States or otherwise introduces a new 
nonroad engine into commerce in the United States. This includes 
importers who import engines or vehicles for resale.
    Maximum test speed has the meaning given in Sec. 1065.610.
    Maximum test torque has the meaning given in Sec. 1065.610.
    Measurement allowance means a specified adjustment in the applicable 
emission standard or a measured emission value to reflect the relative 
quality of the measurement. See the standard-setting part to determine 
whether any measurement allowances apply for your testing. Measurement 
allowances generally apply only for field testing

[[Page 264]]

and are intended to account for reduced accuracy or precision that 
result from using field-grade measurement systems.
    Mode means one of the following:
    (1) A distinct combination of engine speed and load for steady-state 
testing.
    (2) A continuous combination of speeds and loads specifying a 
transition during a ramped-modal test.
    (3) A distinct operator demand setting, such as would occur when 
testing locomotives or constant-speed engines.
    NIST-accepted means relating to a value that has been assigned or 
named by NIST.
    NIST-traceable means relating to a standard value that can be 
related to NIST-stated references through an unbroken chain of 
comparisons, all having stated uncertainties, as specified in NIST 
Technical Note 1297 (incorporated by reference in Sec. 1065.1010). 
Allowable uncertainty limits specified for NIST-traceability refer to 
the propagated uncertainty specified by NIST. You may ask to use other 
internationally recognized standards that are equivalent to NIST 
standards.
    Noise means the precision of 30 seconds of updated recorded values 
from a measurement instrument as it quantifies a zero or reference 
value. Determine instrument noise, repeatability, and accuracy from the 
same data set. We specify a procedure for determining noise in Sec. 
1065.305.
    Nonmethane hydrocarbon equivalent (NMHCE) means the sum of the 
carbon mass contributions of non-oxygenated nonmethane hydrocarbons, 
alcohols and aldehydes, or other organic compounds that are measured 
separately as contained in a gas sample, expressed as exhaust nonmethane 
hydrocarbon from petroleum-fueled engines. The hydrogen-to-carbon ratio 
of the equivalent hydrocarbon is 1.85:1.
    Nonmethane hydrocarbons (NMHC) means the sum of all hydrocarbon 
species except methane. Refer to Sec. 1065.660 for NMHC determination.
    Nonmethane nonethane hydrocarbon (NMNEHC) means the sum of all 
hydrocarbon species except methane and ethane. Refer to Sec. 1065.660 
for NMNEHC determination.
    Nonroad means relating to nonroad engines.
    Nonroad engine has the meaning we give in 40 CFR 1068.30. In general 
this means all internal-combustion engines except motor vehicle engines, 
stationary engines, engines used solely for competition, or engines used 
in aircraft.
    Open crankcase emissions means any flow from an engine's crankcase 
that is emitted directly into the environment. Crankcase emissions are 
not ``open crankcase emissions'' if the engine is designed to always 
route all crankcase emissions back into the engine (for example, through 
the intake system or an aftertreatment system) such that all the 
crankcase emissions, or their products, are emitted into the environment 
only through the engine exhaust system.
    Operator demand means an engine operator's input to control engine 
output. The ``operator'' may be a person (i.e., manual), or a governor 
(i.e., automatic) that mechanically or electronically signals an input 
that demands engine output. Input may be from an accelerator pedal or 
signal, a throttle-control lever or signal, a fuel lever or signal, a 
speed lever or signal, or a governor setpoint or signal. Output means 
engine power, P, which is the product of engine speed, fn, and engine 
torque, T.
    Oxides of nitrogen means NO and NO2 as measured by the 
procedures specified in Sec. 1065.270. Oxides of nitrogen are expressed 
quantitatively as if the NO is in the form of NO2, such that 
you use an effective molar mass for all oxides of nitrogen equivalent to 
that of NO2.
    Oxygenated fuels means fuels composed of at least 25% oxygen-
containing compounds, such as ethanol or methanol. Testing engines that 
use oxygenated fuels generally requires the use of the sampling methods 
in subpart I of this part. However, you should read the standard-setting 
part and subpart I of this part to determine appropriate sampling 
methods.
    Partial pressure means the pressure, p, attributable to a single gas 
in a gas mixture. For an ideal gas, the partial pressure divided by the 
total pressure is equal to the constituent's molar concentration, x.

[[Page 265]]

    Percent (%) means a representation of exactly 0.01. Numbers 
expressed as percentages in this part (such as a tolerance of [2%) have 
infinite precision, so 2% and 2.000000000% have the same meaning. This 
means that where we specify some percentage of a total value, the 
calculated value has the same number of significant digits as the total 
value. For example, 2% of a span value where the span value is 101.3302 
is 2.026604.
    Portable emission measurement system (PEMS) means a measurement 
system consisting of portable equipment that can be used to generate 
brake-specific emission measurements during field testing or laboratory 
testing.
    Precision means two times the standard deviation of a set of 
measured values of a single zero or reference quantity. See also the 
related definitions of noise and repeatability in this section.
    Procedures means all aspects of engine testing, including the 
equipment specifications, calibrations, calculations and other protocols 
and specifications needed to measure emissions, unless we specify 
otherwise.
    Proving ring is a device used to measure static force based on the 
linear relationship between stress and strain in an elastic material. It 
is typically a steel alloy ring, and you measure the deflection (strain) 
of its diameter when a static force (stress) is applied across its 
diameter.
    PTFE means polytetrafluoroethylene, commonly known as Teflon \TM\.
    Purified air means air meeting the specifications for purified air 
in Sec. 1065.750. Purified air may be produced by purifying ambient 
air. The purification may occur at the test site or at another location 
(such as at a gas supplier's facility). Alternatively, purified air may 
be synthetically generated, using good engineering judgment, from 
purified oxygen and nitrogen. The addition of other elements normally 
present in purified ambient air (such as Ar) is not required.
    Ramped-modal means relating to a ramped-modal type of steady-state 
test, as described in the standard-setting part.
    Recommend has the meaning given in Sec. 1065.201.
    Regression statistics means any of the regression statistics 
specified in Sec. 1065.602.
    Repeatability means the precision of ten mean measurements of a 
reference quantity. Determine instrument repeatability, accuracy, and 
noise from the same data set. We specify a procedure for determining 
repeatability in Sec. 1065.305.
    Revoke has the meaning given in 40 CFR 1068.30.
    Rise time, t10-90, means the time interval of a 
measurement instrument's response after any step increase to the input 
between the following points:
    (1) The point at which the response has risen 10% of the total 
amount it will rise in response to the step change.
    (2) The point at which the response has risen 90% of the total 
amount it will rise in response to the step change.
    Roughness (or average roughness, Ra) means the size of finely 
distributed vertical surface deviations from a smooth surface, as 
determined when traversing a surface. It is an integral of the absolute 
value of the roughness profile measured over an evaluation length.
    Round means to apply the rounding convention specified in Sec. 
1065.20(e), unless otherwise specified.
    Scheduled maintenance means adjusting, repairing, removing, 
disassembling, cleaning, or replacing components or systems periodically 
to keep a part or system from failing, malfunctioning, or wearing 
prematurely. It also may mean actions you expect are necessary to 
correct an overt indication of failure or malfunction for which periodic 
maintenance is not appropriate.
    Shared atmospheric pressure meter means an atmospheric pressure 
meter whose output is used as the atmospheric pressure for an entire 
test facility that has more than one dynamometer test cell.
    Shared humidity measurement means a humidity measurement that is 
used as the humidity for an entire test facility that has more than one 
dynamometer test cell.
    Span means to adjust an instrument so that it gives a proper 
response to a calibration standard that represents between 75% and 100% 
of the maximum

[[Page 266]]

value in the instrument range or expected range of use.
    Span gas means a purified gas mixture used to span gas analyzers. 
Span gases must meet the specifications of Sec. 1065.750. Note that 
calibration gases and span gases are qualitatively the same, but differ 
in terms of their primary function. Various performance verification 
checks for gas analyzers and sample handling components might refer to 
either calibration gases or span gases.
    Spark-ignition means relating to a gasoline-fueled engine or any 
other type of engine with a spark plug (or other sparking device) and 
with operating characteristics significantly similar to the theoretical 
Otto combustion cycle. Spark-ignition engines usually use a throttle to 
regulate intake air flow to control power during normal operation.
    Special procedures means procedures allowed under Sec. 
1065.10(c)(2).
    Specified procedures means procedures we specify in this part 1065 
or the standard-setting part. Other procedures allowed or required by 
Sec. 1065.10(c) are not specified procedures.
    Standard deviation has the meaning given in Sec. 1065.602. Note 
this is the standard deviation for a non-biased sample.
    Standard-setting part means the part in the Code of Federal 
Regulations that defines emission standards for a particular engine. See 
Sec. 1065.1(a).
    Steady-state means relating to emission tests in which engine speed 
and load are held at a finite set of nominally constant values. Steady-
state tests are either discrete-mode tests or ramped-modal tests.
    Stoichiometric means relating to the particular ratio of air and 
fuel such that if the fuel were fully oxidized, there would be no 
remaining fuel or oxygen. For example, stoichiometric combustion in a 
gasoline-fueled engine typically occurs at an air-to-fuel mass ratio of 
about 14.7:1.
    Storage medium means a particulate filter, sample bag, or any other 
storage device used for batch sampling.
    t0-50 means the time interval of a measurement system's 
response after any step increase to the input between the following 
points:
    (1) The point at which the step change is initiated at the sample 
probe.
    (2) The point at which the response has risen 50% of the total 
amount it will rise in response to the step change.
    t100-50 means the time interval of a measurement system's 
response after any step decrease to the input between the following 
points:
    (1) The point at which the step change is initiated at the sample 
probe.
    (2) The point at which the response has fallen 50% of the total 
amount it will fall in response to the step change.
    Test engine means an engine in a test sample.
    Test interval means a duration of time over which you determine 
brake-specific emissions. For example, the standard-setting part may 
specify a complete laboratory duty cycle as a cold-start test interval, 
plus a hot-start test interval. As another example, a standard-setting 
part may specify a field-test interval, such as a ``not-to-exceed'' 
(NTE) event, as a duration of time over which an engine operates within 
a certain range of speed and torque. In cases where multiple test 
intervals occur over a duty cycle, the standard-setting part may specify 
additional calculations that weight and combine results to arrive at 
composite values for comparison against the applicable standards.
    Test sample means the collection of engines selected from the 
population of an engine family for emission testing.
    Tolerance means the interval in which at least 95% of a set of 
recorded values of a certain quantity must lie. Use the specified 
recording frequencies and time intervals to determine if a quantity is 
within the applicable tolerance. The concept of tolerance is intended to 
address random variability. You may not take advantage of the tolerance 
specification to incorporate a bias into a measurement.
    Total hydrocarbon (THC) means the combined mass of organic compounds 
measured by the specified procedure for measuring total hydrocarbon, 
expressed as a hydrocarbon with a hydrogen-to-carbon mass ratio of 
1.85:1.
    Total hydrocarbon equivalent (THCE) means the sum of the carbon mass 
contributions of non-oxygenated hydrocarbons, alcohols and aldehydes, or

[[Page 267]]

other organic compounds that are measured separately as contained in a 
gas sample, expressed as exhaust hydrocarbon from petroleum-fueled 
engines. The hydrogen-to-carbon ratio of the equivalent hydrocarbon is 
1.85:1.
    Transformation time, t50, means the overall system 
response time to any step change in input, generally the average of the 
time to reach 50% response to a step increase, t0-50, or to a 
step decrease, t100-50.
    Uncertainty means uncertainty with respect to NIST-traceability. See 
the definition of NIST-traceable in this section.
    United States means the States, the District of Columbia, the 
Commonwealth of Puerto Rico, the Commonwealth of the Northern Mariana 
Islands, Guam, American Samoa, and the U.S. Virgin Islands.
    Useful life means the period during which a new engine is required 
to comply with all applicable emission standards. The standard-setting 
part defines the specific useful-life periods for individual engines.
    Variable-speed engine means an engine that is not a constant-speed 
engine.
    Vehicle means any vehicle, vessel, or type of equipment using 
engines to which this part applies. For purposes of this part, the term 
``vehicle'' may include nonmotive machines or equipment such as a pump 
or generator.
    Verification means to evaluate whether or not a measurement system's 
outputs agree with a range of applied reference signals to within one or 
more predetermined thresholds for acceptance. Contrast with 
``calibration''.
    We (us, our) means the Administrator of the Environmental Protection 
Agency and any authorized representatives.
    Work has the meaning given in Sec. 1065.110.
    Zero means to adjust an instrument so it gives a zero response to a 
zero calibration standard, such as purified nitrogen or purified air for 
measuring concentrations of emission constituents.
    Zero gas means a gas that yields a zero response in an analyzer. 
This may either be purified nitrogen, purified air, a combination of 
purified air and purified nitrogen. For field testing, zero gas may 
include ambient air.

[70 FR 40516, July 13, 2005, as amended at 73 FR 37346, June 30, 2008; 
73 FR 59342, Oct. 8, 2008; 74 FR 8428, Feb. 24, 2009; 74 FR 56518, Oct. 
30, 2009; 75 FR 23058, Apr. 30, 2010; 76 FR 57467, Sept. 15, 2011; 79 FR 
23814, Apr. 28, 2014; 81 FR 74191, Oct. 25, 2016]



Sec. 1065.1005  Symbols, abbreviations, acronyms, and units of measure.

    The procedures in this part generally follow the International 
System of Units (SI), as detailed in NIST Special Publication 811, which 
we incorporate by reference in Sec. 1065.1010. See Sec. 1065.20 for 
specific provisions related to these conventions. This section 
summarizes the way we use symbols, units of measure, and other 
abbreviations.
    (a) Symbols for quantities. This part uses the following symbols and 
units of measure for various quantities:

----------------------------------------------------------------------------------------------------------------
                                                                                           Units in terms of SI
    Symbol              Quantity                   Unit                 Unit symbol             base units
----------------------------------------------------------------------------------------------------------------
a.............  atomic hydrogen-to-      mole per mole..........  mol/mol...............  1.
                 carbon ratio.
A.............  area...................  square meter...........  m\2\..................  m\2\.
a0............  intercept of least
                 squares regression.
a1............  slope of least squares
                 regression.
ag............  acceleration of Earth's  meter per square second  m/s\2\................  m[micro]s-2.
                 gravity.
b.............  ratio of diameters.....  meter per meter........  m/m...................  1.
b.............  atomic oxygen-to-carbon  mole per mole..........  mol/mol...............  1.
                 ratio.
C............  number of carbon atoms
                 in a molecule.
Cd............  discharge coefficient..
Cf............  flow coefficient.......
d.............  atomic nitrogen-to-      mole per mole..........  mol/mol...............  1.
                 carbon ratio.
d.............  Diameter...............  meter..................  m.....................  m.
DR............  dilution ratio.........  mole per mole..........  mol/mol...............  1.
e.............  error between a
                 quantity and its
                 reference.
e.............  brake-specific emission  gram per kilowatt hour.  g/(kW[micro]hr).......  g[micro]3.6[micro]10-6
                 or fuel consumption.                                                      [micro];m-2[middot]
                                                                                           kg-1[micro]s\2\.
F.............  F-test statistic.......
f.............  frequency..............  hertz..................  Hz....................  s-1.
fn............  angular speed (shaft)..  revolutions per minute.  r/min.................  [pi][micro]30-
                                                                                           1[micro]s-1.

[[Page 268]]

 
g.............  ratio of specific heats  (joule per kilogram      (J/(kg[micro]K))/(J/    1.
                                          kelvin) per (joule per   (kg[micro]K)).
                                          kilogram kelvin).
g.............  atomic sulfur-to-carbon  mole per mole..........  mol/mol...............  1.
                 ratio.
K.............  correction factor......  .......................  ......................  1.
Kv............  calibration coefficient  .......................  m\4\[micro];s[micro]K0  m\4\[micro]kg-
                                                                   .5/kg.                  1s[micro]K0.5.
l.............  length.................  meter..................  m.....................  m.
m.............  viscosity, dynamic.....  pascal second..........  Pa[micro]s............  m-1[micro]kg[micro]s-
                                                                                           1.
M.............  molar mass \1\.........  gram per mole..........  g/mol.................  10-
                                                                                           3[micro]kg[micro]mol-
                                                                                           1.
m.............  mass...................  kilogram...............  kg....................  kg.
m.............  mass rate..............  kilogram per second....  kg/s..................  kg[micro]s-1.
n.............  viscosity, kinematic...  meter squared per        m\2\/s................  m\2\[micro]s-1.
                                          second.
N.............  total number in series.
n.............  amount of substance....  mole...................  mol...................  mol.ROW>
n.............  amount of substance      mole per second........  mol/s.................  mol[micro]s-1.
                 rate.
P.............  power..................  kilowatt...............  kW....................  10\3\[micro]m\2\[micro
                                                                                           ]kg[micro]s-3.
PF............  penetration fraction...
p.............  pressure...............  pascal.................  Pa....................  m-1[micro]kg[micro]s-
                                                                                           2.
r.............  mass density...........  kilogram per cubic       kg/m\3\...............  m-3[micro]kg.
                                          meter.
D.............  differential static      pascal.................  Pa....................  m-1[micro]kg[micro]s-
                 pressure.                                                                 2.
r.............  ratio of pressures.....  pascal per pascal......  Pa/Pa.................  1.
r\2\..........  coefficient of
                 determination.
Ra............  average surface          micrometer.............  [micro] m.............  10-6[micro]m.
                 roughness.
Re...........  Reynolds number........
RF............  response factor........
RH............  relative humidity......
s.............  non-biased standard
                 deviation.
S.............  Sutherland constant....  kelvin.................  K.....................  K.
SEE...........  standard estimate of
                 error.
T.............  absolute temperature...  kelvin.................  K.....................  K.
T.............  Celsius temperature....  degree Celsius.........   C....................  K--273.15.
T.............  torque (moment of        newton meter...........  N[micro]m.............  m\2\[micro]kg[micro]s-
                 force).                                                                   2.
[thgr]........  plane angle............  degrees................  ......................  rad.
t.............  time...................  second.................  s.....................  s.
Dt............  time interval, period,   second.................  s.....................  s.
                 1/frequency.
V.............  volume.................  cubic meter............  m\3\..................  m\3\.
V.............  volume rate............  cubic meter per second.  m\3\/s................  m\3\[micro]s-1.
W.............  work...................  kilowatt-hour..........  kW[micro]hr...........  3.6-
                                                                                           1[micro]10\6\[micro]m
                                                                                           \2\[micro]kg[micro]s-
                                                                                           2.
wC............  carbon mass fraction...  gram per gram..........  g/g...................  1.
x.............  amount of substance      mole per mole..........  mol/mol...............  1.
                 mole fraction \2\.
x.............  flow-weighted mean       mole per mole..........  mol/mol...............  1.
                 concentration.
y.............  generic variable.......
Z.............  compressibility factor.
----------------------------------------------------------------------------------------------------------------
\1\ See paragraph (f)(2) of this section for the values to use for molar masses. Note that in the cases of NOX
  and HC, the regulations specify effective molar masses based on assumed speciation rather than actual
  speciation.
\2\ Note that mole fractions for THC, THCE, NMHC, NMHCE, and NOTHC are expressed on a C1-equivalent basis.

    (b) Symbols for chemical species. This part uses the following 
symbols for chemical species and exhaust constituents:

------------------------------------------------------------------------
                Symbol                              Species
------------------------------------------------------------------------
Ar...................................  argon.
C....................................  carbon.
CH2O.................................  formaldehyde.
CH2O2................................  formic acid.
CH3OH................................  methanol.
CH4..................................  methane.
C2H4O................................  acetaldehyde.
C2H5OH...............................  ethanol.
C2H6.................................  ethane.
C3H7OH...............................  propanol.
C3H8.................................  propane.
C4H10................................  butane.
C5H12................................  pentane.
CO...................................  carbon monoxide.
CO2..................................  carbon dioxide.
H....................................  atomic hydrogen.
H2...................................  molecular hydrogen.
H2O..................................  water.
H2SO4................................  sulfuric acid.
HC...................................  hydrocarbon.
He...................................  helium.
\85\Kr...............................  krypton 85.
N2...................................  molecular nitrogen.
NH3..................................  ammonia.
NMHC.................................  nonmethane hydrocarbon.
NMHCE................................  nonmethane hydrocarbon
                                        equivalent.
NMNEHC...............................  nonmethane-nonethane hydrocarbon.
NO...................................  nitric oxide.
NO2..................................  nitrogen dioxide.
NOX..................................  oxides of nitrogen.
N2O..................................  nitrous oxide.
NMOG.................................  nonmethane organic gases.
NONMHC...............................  non-oxygenated nonmethane
                                        hydrocarbon.
NOTHC................................  non-oxygenated total hydrocarbon.
O2...................................  molecular oxygen.
OHC..................................  oxygenated hydrocarbon.
\210\Po..............................  polonium 210.
PM...................................  particulate matter.
S....................................  sulfur.

[[Page 269]]

 
SVOC.................................  semi-volatile organic compound.
THC..................................  total hydrocarbon.
THCE.................................  total hydrocarbon equivalent.
ZrO2.................................  zirconium dioxide.
------------------------------------------------------------------------

    (c) Prefixes. This part uses the following prefixes to define a 
quantity:

------------------------------------------------------------------------
                Symbol                         Quantity           Value
------------------------------------------------------------------------
[micro]..............................  micro...................     10-6
m....................................  milli...................     10-3
c....................................  centi...................     10-2
k....................................  kilo....................    10\3\
M....................................  mega....................    10\6\
------------------------------------------------------------------------

    (d) Superscripts. This part uses the following superscripts to 
define a quantity:

------------------------------------------------------------------------
            Superscript                           Quantity
------------------------------------------------------------------------
overbar (such as y)...............  arithmetic mean.
overdot (such as y)...............  quantity per unit time.
------------------------------------------------------------------------

    (e) Subscripts. This part uses the following subscripts to define a 
quantity:

------------------------------------------------------------------------
             Subscript                            Quantity
------------------------------------------------------------------------
abs...............................  absolute quantity.
act...............................  actual condition.
air...............................  air, dry.
amb...............................  ambient.
atmos.............................  atmospheric.
bkgnd.............................  background.
cal...............................  calibration quantity.
CFV...............................  critical flow venturi.
comb..............................  combined.
composite.........................  composite value.
cor...............................  corrected quantity.
dil...............................  dilution air.
dew...............................  dewpoint.
dexh..............................  diluted exhaust.
dry...............................  dry condition.
dutycycle.........................  duty cycle.
exh...............................  raw exhaust.
exp...............................  expected quantity.
fn................................  feedback speed.
frict.............................  friction.
fuel..............................  fuel consumption.
hi, idle..........................  condition at high-idle.
i.................................  an individual of a series.
idle..............................  condition at idle.
in................................  quantity in.
init..............................  initial quantity, typically before
                                     an emission test.
int...............................  intake air.
j.................................  an individual of a series.
mapped............................  conditions over which an engine can
                                     operate.
max...............................  the maximum (i.e., peak) value
                                     expected at the standard over a
                                     test interval; not the maximum of
                                     an instrument range.
meas..............................  measured quantity.
media.............................  PM sample media.
mix...............................  mixture of diluted exhaust and air.
norm..............................  normalized.
out...............................  quantity out.
P.................................  power.
part..............................  partial quantity.
PDP...............................  positive-displacement pump.
post..............................  after the test interval.
pre...............................  before the test interval.
prod..............................  stoichiometric product.
record............................  record rate.
ref...............................  reference quantity.
rev...............................  revolution.
sat...............................  saturated condition.
s.................................  slip.
span..............................  span quantity.
SSV...............................  subsonic venturi.
std...............................  standard condition.
stroke............................  engine strokes per power stroke.
T.................................  torque.
test..............................  test quantity.
test, alt.........................  alternate test quantity.
uncor.............................  uncorrected quantity.
vac...............................  vacuum side of the sampling system.
weight............................  calibration weight.
zero..............................  zero quantity.
------------------------------------------------------------------------

    (f) Constants. (1) This part uses the following constants for the 
composition of dry air:

------------------------------------------------------------------------
           Symbol                    Quantity               mol/mol
------------------------------------------------------------------------
xArair......................  amount of argon in dry             0.00934
                               air.
xCO2air.....................  amount of carbon                  0.000375
                               dioxide in dry air.
xN2air......................  amount of nitrogen in              0.78084
                               dry air.
xO2air......................  amount of oxygen in               0.209445
                               dry air.
------------------------------------------------------------------------

    (2) This part uses the following molar masses or effective molar 
masses of chemical species:

------------------------------------------------------------------------
                                                        g/mol (10-
         Symbol                  Quantity        3[middot]kg[middot]mol-
                                                            1)
------------------------------------------------------------------------
Mair....................  molar mass of dry air               28.96559
                           \1\.
MAr.....................  molar mass of argon..                 39.948
MC......................  molar mass of carbon.                12.0107
MCH3OH..................  molar mass of                       32.04186
                           methanol.
MC2H5OH.................  molar mass of ethanol               46.06844
MC2H4O..................  molar mass of                       44.05256
                           acetaldehyde.
MCH4N2O.................  molar mass of urea...               60.05526
MC3H8...................  molar mass of propane               44.09562
MC3H7OH.................  molar mass of                       60.09502
                           propanol.
MCO.....................  molar mass of carbon                 28.0101
                           monoxide.

[[Page 270]]

 
MCH4....................  molar mass of methane                16.0425
MCO2....................  molar mass of carbon                 44.0095
                           dioxide.
MH......................  molar mass of atomic                 1.00794
                           hydrogen.
MH2.....................  molar mass of                        2.01588
                           molecular hydrogen.
MH2O....................  molar mass of water..               18.01528
MCH2O...................  molar mass of                       30.02598
                           formaldehyde.
MHe.....................  molar mass of helium.               4.002602
MN......................  molar mass of atomic                 14.0067
                           nitrogen.
MN2.....................  molar mass of                        28.0134
                           molecular nitrogen.
MNH3....................  molar mass of ammonia               17.03052
MNMHC...................  effective C1 molar                 13.875389
                           mass of nonmethane
                           hydrocarbon \2\.
MNMHCE..................  effective C1 molar                 13.875389
                           mass of nonmethane
                           hydrocarbon
                           equivalent \2\.
MNMNEHC.................  effective C1 molar                 13.875389
                           mass of nonmethane-
                           nonethane
                           hydrocarbon \2\.
MNOx....................  effective molar mass                 46.0055
                           of oxides of
                           nitrogen \3\.
MN2O....................  molar mass of nitrous                44.0128
                           oxide.
MO......................  molar mass of atomic                 15.9994
                           oxygen.
MO2.....................  molar mass of                        31.9988
                           molecular oxygen.
MS......................  molar mass of sulfur.                 32.065
MTHC....................  effective C1 molar                 13.875389
                           mass of total
                           hydrocarbon \2\.
MTHCE...................  effective C1 molar                 13.875389
                           mass of total
                           hydrocarbon
                           equivalent \2\.
------------------------------------------------------------------------
\1\ See paragraph (f)(1) of this section for the composition of dry air.
\2\ The effective molar masses of THC, THCE, NMHC, NMHCE, and NMNEHC are
  defined on a C1 basis and are based on an atomic hydrogen-to-carbon
  ratio, a, of 1.85 (with b, g, and d equal to zero).
\3\ The effective molar mass of NOX is defined by the molar mass of
  nitrogen dioxide, NO2.

    (3) This part uses the following molar gas constant for ideal gases:

------------------------------------------------------------------------
                                                      J/(mol [middot] K)
                                                       (m\2\ [middot] kg
           Symbol                    Quantity            [middot] s-2
                                                        [middot] mol-1
                                                         [middot] K-1)
------------------------------------------------------------------------
R...........................  molar gas constant....            8.314472
------------------------------------------------------------------------

    (4) This part uses the following ratios of specific heats for 
dilution air and diluted exhaust:

------------------------------------------------------------------------
                                                        [J/(kg [middot]
           Symbol                    Quantity             K)]/[J/(kg
                                                         [middot] K)]
------------------------------------------------------------------------
gair........................  ratio of specific                    1.399
                               heats for intake air
                               or dilution air.
gdil........................  ratio of specific                    1.399
                               heats for diluted
                               exhaust.
gexh........................  ratio of specific                    1.385
                               heats for raw exhaust.
------------------------------------------------------------------------

    (g) Other acronyms and abbreviations. This part uses the following 
additional abbreviations and acronyms:

------------------------------------------------------------------------
 
------------------------------------------------------------------------
ABS...............................  acrylonitrile-butadiene-styrene.
ASTM..............................  American Society for Testing and
                                     Materials.
BMD...............................  bag mini-diluter.
BSFC..............................  brake-specific fuel consumption.
CARB..............................  California Air Resources Board.
CFR...............................  Code of Federal Regulations.
CFV...............................  critical-flow venturi.
CI................................  compression-ignition.
CITT..............................  Curb Idle Transmission Torque.
CLD...............................  chemiluminescent detector.
CVS...............................  constant-volume sampler.
DF................................  deterioration factor.
ECM...............................  electronic control module.
EFC...............................  electronic flow control.
e.g...............................  for example.
EGR...............................  exhaust gas recirculation.
EPA...............................  Environmental Protection Agency.
FEL...............................  Family Emission Limit.
FID...............................  flame-ionization detector.
FTIR..............................  Fourier transform infrared.
GC................................  gas chromatograph.
GC-ECD............................  gas chromatograph with an electron-
                                     capture detector.
GC-FID............................  gas chromatograph with a flame
                                     ionization detector.
HEPA..............................  high-efficiency particulate air.
IBP...............................  initial boiling point.
IBR...............................  incorporated by reference.
i.e...............................  in other words.
ISO...............................  International Organization for
                                     Standardization.
LPG...............................  liquefied petroleum gas.
MPD...............................  magnetopneumatic detection.
NDIR..............................  nondispersive infrared.
NDUV..............................  nondispersive ultraviolet.
NIST..............................  National Institute for Standards and
                                     Technology.
NMC...............................  nonmethane cutter.
PDP...............................  positive-displacement pump.
PEMS..............................  portable emission measurement
                                     system.
PFD...............................  partial-flow dilution.
PLOT..............................  porous layer open tubular.
PMD...............................  paramagnetic detection.
PMP...............................  Polymethylpentene.
pt................................  a single point at the mean value
                                     expected at the standard.
psi...............................  pounds per square inch.
PTFE..............................  polytetrafluoroethylene (commonly
                                     known as Teflon \TM\).
RE................................  rounding error.
RESS..............................  rechargeable energy storage system.
RFPF..............................  response factor penetration
                                     fraction.

[[Page 271]]

 
RMC...............................  ramped-modal cycle.
rms...............................  root-mean square.
RTD...............................  resistive temperature detector.
SAW...............................  surface acoustic wave.
SEE...............................  standard estimate of error.
SSV...............................  subsonic venturi.
SI................................  spark-ignition.
THC-FID...........................  total hydrocarbon flame ionization
                                     detector.
TINV..............................  inverse student t-test function in
                                     Microsoft Excel.
UCL...............................  upper confidence limit.
UFM...............................  ultrasonic flow meter.
U.S.C.............................  United States Code.
------------------------------------------------------------------------


[79 FR 23815, Apr. 28, 2014, as amended at 81 FR 74191, Oct. 25, 2016]



Sec. 1065.1010  Incorporation by reference.

    (a) Certain material is incorporated by reference into this part 
with the approval of the Director of the Federal Register under 5 U.S.C. 
552(a) and 1 CFR part 51. To enforce any edition other than that 
specified in this section, a document must be published in the Federal 
Register and the material must be available to the public. All approved 
materials are available for inspection at the Air and Radiation Docket 
and Information Center (Air Docket) in the EPA Docket Center (EPA/DC) at 
Rm. 3334, EPA West Bldg., 1301 Constitution Ave. NW., Washington, DC. 
The EPA/DC Public Reading Room hours of operation are 8:30 a.m. to 4:30 
p.m., Monday through Friday, excluding legal holidays. The telephone 
number of the EPA/DC Public Reading Room is (202) 566-1744, and the 
telephone number for the Air Docket is (202) 566-1742. These approved 
materials are also available for inspection at the National Archives and 
Records Administration (NARA). For information on the availability of 
this material at NARA, call (202) 741-6030 or go to http://
www.archives.gov/federal--register/code--of--federal--regulations/ibr--
locations.html. In addition, these materials are available from the 
sources listed below.
    (b) ASTM material. The following standards are available from ASTM 
International, 100 Barr Harbor Dr., P.O. Box C700, West Conshohocken, PA 
19428-2959, (877) 909-2786, or http://www.astm.org:

    (1) ASTM D86-12, Standard Test Method for Distillation of Petroleum 
Products at Atmospheric Pressure, approved December 1, 2012 (``ASTM 
D86''), IBR approved for Sec. Sec. 1065.703(b) and 1065.710(b) and (c).
    (2) ASTM D93-13, Standard Test Methods for Flash Point by Pensky-
Martens Closed Cup Tester, approved July 15, 2013 (``ASTM D93''), IBR 
approved for Sec. 1065.703(b).
    (3) ASTM D130-12, Standard Test Method for Corrosiveness to Copper 
from Petroleum Products by Copper Strip Test, approved November 1, 2012 
(``ASTM D130''), IBR approved for Sec. 1065.710(b).
    (4) ASTM D381-12, Standard Test Method for Gum Content in Fuels by 
Jet Evaporation, approved April 15, 2012 (``ASTM D381''), IBR approved 
for Sec. 1065.710(b).
    (5) ASTM D445-12, Standard Test Method for Kinematic Viscosity of 
Transparent and Opaque Liquids (and Calculation of Dynamic Viscosity), 
approved April 15, 2012 (``ASTM D445''), IBR approved for Sec. 
1065.703(b).
    (6) ASTM D525-12a, Standard Test Method for Oxidation Stability of 
Gasoline (Induction Period Method), approved September 1, 2012 (``ASTM 
D525''), IBR approved for Sec. 1065.710(b).
    (7) ASTM D613-13, Standard Test Method for Cetane Number of Diesel 
Fuel Oil, approved December 1, 2013 (``ASTM D613''), IBR approved for 
Sec. 1065.703(b).
    (8) ASTM D910-13a, Standard Specification for Aviation Gasolines, 
approved December 1, 2013 (``ASTM D910''), IBR approved for Sec. 
1065.701(f).
    (9) ASTM D975-13a, Standard Specification for Diesel Fuel Oils, 
approved December 1, 2013 (``ASTM D975''), IBR approved for Sec. 
1065.701(f).
    (10) ASTM D1267-12, Standard Test Method for Gage Vapor Pressure of 
Liquefied Petroleum (LP) Gases (LP-Gas Method), approved November 1, 
2012 (``ASTM D1267''), IBR approved for Sec. 1065.720(a).
    (11) ASTM D1319-13, Standard Test Method for Hydrocarbon Types in 
Liquid Petroleum Products by Fluorescent Indicator Adsorption, approved 
May 1, 2013 (``ASTM D1319''), IBR approved for Sec. 1065.710(c).
    (12) ASTM D1655-13a, Standard Specification for Aviation Turbine 
Fuels, approved December 1, 2013 (``ASTM D1655''), IBR approved for 
Sec. 1065.701(f).
    (13) ASTM D1837-11, Standard Test Method for Volatility of Liquefied 
Petroleum (LP) Gases, approved October 1, 2011 (``ASTM D1837''), IBR 
approved for Sec. 1065.720(a).
    (14) ASTM D1838-12a, Standard Test Method for Copper Strip Corrosion 
by Liquefied Petroleum (LP) Gases, approved December 1, 2012 (``ASTM 
D1838''), IBR approved for Sec. 1065.720(a).
    (15) ASTM D1945-03 (Reapproved 2010), Standard Test Method for 
Analysis of Natural Gas by Gas Chromatography, approved January 1, 2010 
(``ASTM D1945''), IBR approved for Sec. 1065.715(a).
    (16) ASTM D2158-11, Standard Test Method for Residues in Liquefied 
Petroleum (LP)

[[Page 272]]

Gases, approved January 1, 2011 (``ASTM D2158''), IBR approved for Sec. 
1065.720(a).
    (17) ASTM D2163-07, Standard Test Method for Determination of 
Hydrocarbons in Liquefied Petroleum (LP) Gases and Propane/Propene 
Mixtures by Gas Chromatography, approved December 1, 2007 (``ASTM 
D2163''), IBR approved for Sec. 1065.720(a).
    (18) ASTM D2598-12, Standard Practice for Calculation of Certain 
Physical Properties of Liquefied Petroleum (LP) Gases from Compositional 
Analysis, approved November 1, 2012 (``ASTM D2598''), IBR approved for 
Sec. 1065.720(a).
    (19) ASTM D2622-10, Standard Test Method for Sulfur in Petroleum 
Products by Wavelength Dispersive X-ray Fluorescence Spectrometry, 
approved February 15, 2010 (``ASTM D2622''), IBR approved for Sec. Sec. 
1065.703(b) and 1065.710(b) and (c).
    (20) ASTM D2699-13b, Standard Test Method for Research Octane Number 
of Spark-Ignition Engine Fuel, approved October 1, 2013 (``ASTM 
D2699''), IBR approved for Sec. 1065.710(b).
    (21) ASTM D2700-13b, Standard Test Method for Motor Octane Number of 
Spark-Ignition Engine Fuel, approved October 1, 2013 (``ASTM D2700''), 
IBR approved for Sec. 1065.710(b).
    (22) ASTM D2713-13, Standard Test Method for Dryness of Propane 
(Valve Freeze Method), approved October 1, 2013 (``ASTM D2713''), IBR 
approved for Sec. 1065.720(a).
    (23) ASTM D2784-11, Standard Test Method for Sulfur in Liquefied 
Petroleum Gases (Oxy-Hydrogen Burner or Lamp), approved January 1, 2011 
(``ASTM D2784''), IBR approved for Sec. 1065.720(a).
    (24) ASTM D2880-13b, Standard Specification for Gas Turbine Fuel 
Oils, approved November 15, 2013 (``ASTM D2880''), IBR approved for 
Sec. 1065.701(f).
    (25) ASTM D2986-95a, Standard Practice for Evaluation of Air Assay 
Media by the Monodisperse DOP (Dioctyl Phthalate) Smoke Test, approved 
September 10, 1995 (``ASTM D2986''), IBR approved for Sec. 1065.170(c). 
(Note: This standard was withdrawn by ASTM.)
    (26) ASTM D3231-13, Standard Test Method for Phosphorus in Gasoline, 
approved June 15, 2013 (``ASTM D3231''), IBR approved for Sec. 
1065.710(b) and (c).
    (27) ASTM D3237-12, Standard Test Method for Lead in Gasoline By 
Atomic Absorption Spectroscopy, approved June 1, 2012 (``ASTM D3237''), 
IBR approved for Sec. 1065.710(b) and (c).
    (28) ASTM D4052-11, Standard Test Method for Density, Relative 
Density, and API Gravity of Liquids by Digital Density Meter, approved 
October 15, 2011 (``ASTM D4052''), IBR approved for Sec. 1065.703(b).
    (29) ASTM D4629-12, Standard Test Method for Trace Nitrogen in 
Liquid Petroleum Hydrocarbons by Syringe/Inlet Oxidative Combustion and 
Chemiluminescence Detection, approved April 15, 2012 (``ASTM D4629''), 
IBR approved for Sec. 1065.655(e).
    (30) ASTM D4814-13b, Standard Specification for Automotive Spark-
Ignition Engine Fuel, approved December 1, 2013 (``ASTM D4814''), IBR 
approved for Sec. 1065.701(f).
    (31) ASTM D4815-13, Standard Test Method for Determination of MTBE, 
ETBE, TAME, DIPE, tertiary-Amyl Alcohol and C1 to 
C4 Alcohols in Gasoline by Gas Chromatography, approved 
October 1, 2013 (``ASTM D4815''), IBR approved for Sec. 1065.710(b).
    (32) ASTM D5186-03 (Reapproved 2009), Standard Test Method for 
Determination of the Aromatic Content and Polynuclear Aromatic Content 
of Diesel Fuels and Aviation Turbine Fuels By Supercritical Fluid 
Chromatography, approved April 15, 2009 (``ASTM D5186''), IBR approved 
for Sec. 1065.703(b).
    (33) ASTM D5191-13, Standard Test Method for Vapor Pressure of 
Petroleum Products (Mini Method), approved December 1, 2013 (``ASTM 
D5191''), IBR approved for Sec. 1065.710(b) and (c).
    (34) ASTM D5291-10, Standard Test Methods for Instrumental 
Determination of Carbon, Hydrogen, and Nitrogen in Petroleum Products 
and Lubricants, approved May 1, 2010 (``ASTM D5291''), IBR approved for 
Sec. 1065.655(e).
    (35) ASTM D5453-12, Standard Test Method for Determination of Total 
Sulfur in Light Hydrocarbons, Spark Ignition Engine Fuel, Diesel Engine 
Fuel, and Engine Oil by Ultraviolet Fluorescence, approved November 1, 
2012 (``ASTM D5453''), IBR approved for Sec. 1065.710(b).
    (36) ASTM D5599-00 (Reapproved 2010), Standard Test Method for 
Determination of Oxygenates in Gasoline by Gas Chromatography and Oxygen 
Selective Flame Ionization Detection, approved October 1, 2010 (``ASTM 
D5599''), IBR approved for Sec. Sec. 1065.655(e) and 1065.710(b).
    (37) ASTM D5762-12 Standard Test Method for Nitrogen in Petroleum 
and Petroleum Products by Boat-Inlet Chemiluminescence, approved April 
15, 2012 (``ASTM D5762''), IBR approved for Sec. 1065.655(e).
    (38) ASTM D5769-10, Standard Test Method for Determination of 
Benzene, Toluene, and Total Aromatics in Finished Gasolines by Gas 
Chromatography/Mass Spectrometry, approved May 1, 2010 (``ASTM D5769''), 
IBR approved for Sec. 1065.710(b).
    (39) ASTM D5797-13, Standard Specification for Fuel Methanol (M70- 
M85) for Automotive Spark-Ignition Engines, approved June 15, 2013 
(``ASTM D5797''), IBR approved for Sec. 1065.701(f).
    (40) ASTM D5798-13a, Standard Specification for Ethanol Fuel Blends 
for Flexible Fuel Automotive Spark-Ignition Engines, approved June 15, 
2013 (``ASTM D5798''), IBR approved for Sec. 1065.701(f).
    (41) ASTM D6348-12 [egr]1, Standard Test Method for Determination of 
Gaseous Compounds

[[Page 273]]

by Extractive Direct Interface Fourier Transform Infrared (FTIR) 
Spectroscopy, approved February 1, 2012 (``ASTM D6348''), IBR approved 
for Sec. Sec. 1065.266(b) and 1065.275(b).
    (42) ASTM D6550-10, Standard Test Method for Determination of Olefin 
Content of Gasolines by Supercritical-Fluid Chromatography, approved 
October 1, 2010 (``ASTM D6550''), IBR approved for Sec. 1065.710(b).
    (43) ASTM D6615-11a, Standard Specification for Jet B Wide-Cut 
Aviation Turbine Fuel, approved October 1, 2011 (``ASTM D6615''), IBR 
approved for Sec. 1065.701(f).
    (44) ASTM D6751-12, Standard Specification for Biodiesel Fuel Blend 
Stock (B100) for Middle Distillate Fuels, approved August 1, 2012 
(``ASTM D6751''), IBR approved for Sec. 1065.701(f).
    (45) ASTM D6985-04a, Standard Specification for Middle Distillate 
Fuel Oil--Military Marine Applications, approved November 1, 2004 
(``ASTM D6985''), IBR approved for Sec. 1065.701(f). (Note: This 
standard was withdrawn by ASTM.)
    (46) ASTM D7039-13, Standard Test Method for Sulfur in Gasoline, 
Diesel Fuel, Jet Fuel, Kerosine, Biodiesel, Biodiesel Blends, and 
Gasoline-Ethanol Blends by Monochromatic Wavelength Dispersive X-ray 
Fluorescence Spectrometry, approved September 15, 2013 (``ASTM D7039''), 
IBR approved for Sec. 1065.710(b).
    (47) ASTM F1471-09, Standard Test Method for Air Cleaning 
Performance of a High- Efficiency Particulate Air Filter System, 
approved March 1, 2009 (``ASTM F1471''), IBR approved for Sec. 
1065.1001.
    (c) California Air Resources Board material. The following documents 
are available from the California Air Resources Board, Haagen-Smit 
Laboratory, 9528 Telstar Ave., El Monte, CA 91731-2908, (800) 242-4450, 
or http://www.arb.ca.gov:
    (1) California Non-Methane Organic Gas Test Procedures, Amended July 
30, 2002, Mobile Source Division, California Air Resources Board, IBR 
approved for Sec. 1065.805(f).
    (2) [Reserved]
    (d) Institute of Petroleum material. The following documents are 
available from the Energy Institute, 61 New Cavendish St., London, W1G 
7AR, UK, or by calling + 44-(0)20-7467-7100, or at http://
www.energyinst.org:
    (1) IP-470, 2005, Determination of aluminum, silicon, vanadium, 
nickel, iron, calcium, zinc, and sodium in residual fuels by atomic 
absorption spectrometry, IBR approved for Sec. 1065.705(b).
    (2) IP-500, 2003, Determination of the phosphorus content of 
residual fuels by ultra-violet spectrometry, IBR approved for Sec. 
1065.705(b).
    (3) IP-501, 2005, Determination of aluminum, silicon, vanadium, 
nickel, iron, sodium, calcium, zinc and phosphorus in residual fuel oil 
by ashing, fusion and inductively coupled plasma emission spectrometry, 
IBR approved for Sec. 1065.705(b).
    (e) ISO material. The following standards are available from the 
International Organization for Standardization, 1, ch. de la Voie-
Creuse, CP 56, CH-1211 Geneva 20, Switzerland, 41-22-749-01-11, or 
http://www.iso.org:

    (1) ISO 2719:2002, Determination of flash point--Pensky-Martens 
closed cup method (``ISO 2719''), IBR approved for Sec. 1065.705(c).
    (2) ISO 3016:1994, Petroleum products--Determination of pour point 
(``ISO 3016''), IBR approved for Sec. 1065.705(c).
    (3) ISO 3104:1994/Cor 1:1997, Petroleum products--Transparent and 
opaque liquids--Determination of kinematic viscosity and calculation of 
dynamic viscosity (``ISO 3104''), IBR approved for Sec. 1065.705(c).
    (4) ISO 3675:1998, Crude petroleum and liquid petroleum products--
Laboratory determination of density--Hydrometer method (``ISO 3675''), 
IBR approved for Sec. 1065.705(c).
    (5) ISO 3733:1999, Petroleum products and bituminous materials--
Determination of water--Distillation method (``ISO 3733''), IBR approved 
for Sec. 1065.705(c).
    (6) ISO 6245:2001, Petroleum products--Determination of ash (``ISO 
6245''), IBR approved for Sec. 1065.705(c).
    (7) ISO 8217:2012(E), Petroleum products--Fuels (class F)--
Specifications of marine fuels, Fifth edition, August 15, 2012 (``ISO 
8217''), IBR approved for Sec. 1065.705(b) and (c).
    (8) ISO 8754:2003, Petroleum products--Determination of sulfur 
content--Energy-dispersive X-ray Fluorescence spectrometry (``ISO 
8754''), IBR approved for Sec. 1065.705(c).
    (9) ISO 10307-2(E):2009, Petroleum products--Total sediment in 
residual fuel oils--Part 2: Determination using standard procedures for 
ageing, Second Ed., February 1, 2009 (``ISO 10307''), as modified by ISO 
10307-2:2009/Cor.1:2010(E), Technical Corrigendum 1, published May 15, 
2010, IBR approved for Sec. 1065.705(c).
    (10) ISO 10370:1993/Cor 1:1996, Petroleum products--Determination of 
carbon residue--Micro method (``ISO 10370''), IBR approved for Sec. 
1065.705(c).
    (11) ISO 10478:1994, Petroleum products--Determination of aluminium 
and silicon in fuel oils--Inductively coupled plasma emission and atomic 
absorption spectroscopy methods (``ISO 10478''), IBR approved for Sec. 
1065.705(c).

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    (12) ISO 12185:1996/Cor 1:2001, Crude petroleum and petroleum 
products--Determination of density--Oscillating U-tube method (``ISO 
12185''), IBR approved for Sec. 1065.705(c).
    (13) ISO 14596:2007, Petroleum products--Determination of sulfur 
content--Wavelength-dispersive X-ray fluorescence spectrometry (``ISO 
14596''), IBR approved for Sec. 1065.705(c).
    (14) ISO 14597:1997, Petroleum products--Determination of vanadium 
and nickel content--Wavelength dispersive X-ray fluorescence 
spectrometry (``ISO 14597''), IBR approved for Sec. 1065.705(c).
    (15) ISO 14644-1:1999, Cleanrooms and associated controlled 
environments (``ISO 14644''), IBR approved for Sec. 1065.190(b).
    (f) NIST material. The following documents are available from 
National Institute of Standards and Technology, 100 Bureau Drive, Stop 
1070, Gaithersburg, MD 20899-1070, (301) 975-6478, or www.nist.gov:
    (1) NIST Special Publication 811, 2008 Edition, Guide for the Use of 
the International System of Units (SI), March 2008, IBR approved for 
Sec. Sec. 1065.20(a) and 1065.1005.
    (2) NIST Technical Note 1297, 1994 Edition, Guidelines for 
Evaluating and Expressing the Uncertainty of NIST Measurement Results, 
IBR approved for Sec. 1065.1001.
    (g) SAE International material. The following standards are 
available from SAE International, 400 Commonwealth Dr., Warrendale, PA 
15096-0001, (724) 776-4841, or http://www.sae.org:
    (1) SAE 770141, 1977, Optimization of Flame Ionization Detector for 
Determination of Hydrocarbon in Diluted Automotive Exhausts, Glenn D. 
Reschke, IBR approved for Sec. 1065.360(c).
    (2) SAE J1151, Methane Measurement Using Gas Chromatography, 
stabilized September 2011, IBR approved for Sec. Sec. 1065.267(b) and 
1065.750(a).

[79 FR 23818, Apr. 28, 2014, as amended at 81 FR 74193, Oct. 25, 2016]



        Subpart L_Methods for Unregulated and Special Pollutants

    Source: 79 FR 23820, Apr. 28, 2014, unless otherwise noted.



Sec. 1065.1101  Applicability.

    This subpart specifies procedures that may be used to measure 
emission constituents that are not measured (or not separately measured) 
by the test procedures in the other subparts of this part. These 
procedures are included to facilitate consistent measurement of 
unregulated pollutants for purposes other than compliance with emission 
standards. Unless otherwise specified in the standard-setting part, use 
of these procedures is optional and does not replace any requirements in 
the rest of this part.

                     Semi-Volatile Organic Compounds



Sec. 1065.1103  General provisions for SVOC measurement.

    The provisions of Sec. Sec. 1065.1103 through 1065.1111 specify 
procedures for measuring semi-volatile organic compounds (SVOC) along 
with PM. These sections specify how to collect a sample of the SVOCs 
during exhaust emission testing, as well as how to use wet chemistry 
techniques to extract SVOCs from the sample media for analysis. Note 
that the precise method you use will depend on the category of SVOCs 
being measured. For example, the method used to measure polynuclear 
aromatic hydrocarbons (PAHs) will differ slightly from the method used 
to measure dioxins. Follow standard analytic chemistry methods for any 
aspects of the analysis that are not specified.
    (a) Laboratory cleanliness is especially important throughout SVOC 
testing. Thoroughly clean all sampling system components and glassware 
before testing to avoid sample contamination. For the purposes of this 
subpart, the sampling system is defined as sample pathway from the 
sample probe inlet to the downstream most point where the sample is 
captured (in this case the condensate trap).
    (b) We recommend that media blanks be analyzed for each batch of 
sample media (sorbent, filters, etc.) prepared for testing. Blank 
sorbent modules (i.e., field blanks) should be stored in a sealed 
environment and should periodically accompany the test sampling system 
throughout the course of a test, including sampling system and sorbent 
module disassembly, sample packaging, and storage. Use good engineering 
judgment to determine the frequency with which you should generate field 
blanks. The field blank sample

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should be close to the sampler during testing.
    (c) We recommend the use of isotope dilution techniques, including 
the use of isotopically labeled surrogate, internal, alternate, and 
injection standards.
    (d) If your target analytes degrade when exposed to ultraviolet 
radiation, such as nitropolynuclear aromatic hydrocarbons (nPAHs), 
perform these procedures in the dark or with ultraviolet filters 
installed over the lights.
    (e) The following definitions and abbreviations apply for SVOC 
measurements:
    (1) Soxhlet extraction means the extraction method invented by Franz 
von Soxhlet, in which the sample is placed in a thimble and rinsed 
repeatedly with a recycle of the extraction solvent.
    (2) XAD-2 means a hydrophobic crosslinked polystyrene copolymer 
resin adsorbent known commercially as Amberlitecaret 
XADcaret-2, or an equivalent adsorbent like XAD-4.
    (3) Semi-volatile organic compound (SVOC) means an organic compound 
that is sufficiently volatile to exist in vapor form in engine exhaust, 
but that readily condenses to liquid or solid form under atmospheric 
conditions. Most SVOCs have at least 14 carbon atoms per molecule or 
they have a boiling point between (240 and 400)  deg.C. SVOCs include 
dioxin, quinone, and nitro-PAH compounds. They may be a natural 
byproduct of combustion or they may be created post-combustion. Note 
that SVOCs may be included in measured values of hydrocarbons and/or PM 
using the procedures specified in this part.
    (4) Kuderna-Danish concentrator means laboratory glassware known by 
this name that consists of an air-cooled condenser on top of an 
extraction bulb.
    (5) Dean-Stark trap means laboratory glassware known by this name 
that uses a reflux condenser to collect water from samples extracted 
under reflux.
    (6) PUF means polyurethane foam.
    (7) Isotopically labeled means relating to a compound in which 
either all the hydrogen atoms are replaced with the atomic isotope 
hydrogen-2 (deuterium) or one of the carbon atoms at a defined position 
in the molecule is replaced with the atomic isotope carbon-13.



Sec. 1065.1105  Sampling system design.

    (a) General. We recommend that you design your SVOC batch sampler to 
extract sample from undiluted emissions to maximize the sampled SVOC 
quantity. If you dilute your sample, we recommend using annular 
dilution. If you dilute your sample, but do not use annular dilution, 
you must precondition your sampling system to reach equilibrium with 
respect to loss and re-entrainment of SVOCs to the walls of the sampling 
system. To the extent practical, adjust sampling times based on the 
emission rate of target analytes from the engine to obtain analyte 
concentrations above the detection limit. In some instances you may need 
to run repeat test cycles without replacing the sample media or 
disassembling the batch sampler.
    (b) Sample probe, transfer lines, and sample media holder design and 
construction. The sampling system should consist of a sample probe, 
transfer line, PM filter holder, cooling coil, sorbent module, and 
condensate trap. Construct sample probes, transfer lines, and sample 
media holders that have inside surfaces of nickel, titanium or another 
nonreactive material capable of withstanding raw exhaust gas 
temperatures. Seal all joints in the hot zone of the system with gaskets 
made of nonreactive material similar to that of the sampling system 
components. You may use teflon gaskets in the cold zone. We recommend 
locating all components as close to probes as practical to shorten 
sampling system length and minimize the surface exposed to engine 
exhaust.
    (c) Sample system configuration. This paragraph (c) specifies the 
components necessary to collect SVOC samples, along with our recommended 
design parameters. Where you do not follow our recommendations, use good 
engineering judgment to design your sampling system so it does not 
result in loss of SVOC during sampling. The sampling system should 
contain the following components in series in the order listed:
    (1) Use a sample probe similar to the PM sample probe specified in 
subpart B of this part.
    (2) Use a PM filter holder similar to the holder specified in 
subpart B of this part, although you will likely need to

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use a larger size to accommodate the high sample flow rates. We 
recommend using a 110 mm filter for testing spark ignition engines or 
engines that utilize exhaust aftertreatment for PM removal and a 293 mm 
filter for other engines. If you are not analyzing separately for SVOCs 
in gas and particle phases, you do not have to control the temperature 
of the filter holder. Note that this differs from normal PM sampling 
procedures, which maintain the filter at a much lower temperature to 
capture a significant fraction of exhaust SVOC on the filter. In this 
method, SVOCs that pass through the filter will be collected on the 
downstream sorbent module. If you are collecting SVOCs in gas and 
particle phases, control your filter face temperature according to Sec. 
1065.140(e)(4).
    (3) Use good engineering judgment to design a cooling coil that will 
drop the sample temperature to approximately 5  deg.C. Note that 
downstream of the cooling coil, the sample will be a mixture of vapor 
phase hydrocarbons in CO2, air, and a primarily aqueous 
liquid phase.
    (4) Use a hydrophobic sorbent in a sealed sorbent module. Note that 
this sorbent module is intended to be the final stage for collecting the 
SVOC sample and should be sized accordingly. We recommend sizing the 
module to hold 40 g of XAD-2 along with PUF plugs at either end of the 
module, noting that you may vary the mass of XAD used for testing based 
on the anticipated SVOC emission concentration and sample flow rate.
    (5) Include a condensate trap to separate the aqueous liquid phase 
from the gas stream. We recommend using a peristaltic pump to remove 
water from the condensate trap over the course of the test to prevent 
build-up of the condensate. Note that for some tests it may be 
appropriate to collect this water for analysis.
    (d) Sampler flow control. For testing using the recommended filter 
and sorbent module sizes, we recommend targeting an average sample flow 
rate of 70 liters per minute to maximize SVOC collection. The sampler 
must be designed to maintain proportional sampling throughout the test. 
Verify proportional sampling after an emission test as described in 
Sec. 1065.545.
    (e) Water bath. Design the sample system with a water bath in which 
the cooling coil, sorbent module, and condensate trap will be submerged. 
Use a heat exchanger or ice to maintain the bath temperature at (3 to 7) 
 deg.C.

[79 FR 23820, Apr. 28, 2014, as amended at 81 FR 74195, Oct. 25, 2016]



Sec. 1065.1107  Sample media and sample system preparation; 
sample system assembly.

    This section describes the appropriate types of sample media and the 
cleaning procedure required to prepare the media and wetted sample 
surfaces for sampling.
    (a) Sample media. The sampling system uses two types of sample media 
in series: The first to simultaneously capture the PM and associated 
particle phase SVOCs, and a second to capture SVOCs that remain in the 
gas phase, as follows:
    (1) For capturing PM, we recommend using pure quartz filters with no 
binder if you are not analyzing separately for SVOCs in gas and particle 
phases. If you are analyzing separately, you must use 
polytetrafluoroethylene (PTFE) filters with